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Molecules, Volume 19, Issue 4 (April 2014), Pages 3851-5458

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Open AccessArticle N-Substituted 2-Isonicotinoylhydrazinecarboxamides — New Antimycobacterial Active Molecules
Molecules 2014, 19(4), 3851-3868; doi:10.3390/molecules19043851
Received: 28 February 2014 / Revised: 21 March 2014 / Accepted: 24 March 2014 / Published: 28 March 2014
Cited by 2 | PDF Full-text (577 KB) | HTML Full-text | XML Full-text
Abstract
This report presents a new modification of the isoniazid (INH) structure linked with different anilines via a carbonyl group obtained by two synthetic procedures and with N-substituted 5-(pyridine-4-yl)-1,3,4-oxadiazole-2-amines prepared by their cyclisation. All synthesised derivatives were characterised by IR, NMR, MS [...] Read more.
This report presents a new modification of the isoniazid (INH) structure linked with different anilines via a carbonyl group obtained by two synthetic procedures and with N-substituted 5-(pyridine-4-yl)-1,3,4-oxadiazole-2-amines prepared by their cyclisation. All synthesised derivatives were characterised by IR, NMR, MS and elemental analyses and were evaluated in vitro for their antimycobacterial activity against Mycobacterium tuberculosis H37Rv, Mycobacterium avium 330/88, Mycobacterium kansasii 235/80 and one clinical isolated strain of M. kansasii 6509/96. 2-Isonicotinoyl-N-(4-octylphenyl)hydrazinecarboxamide displayed an in vitro efficacy comparable to that of INH for M. tuberculosis with minimum inhibitory concentrations (MICs) of 1–2 μM. Among the halogenated derivatives, the best anti-tuberculosis activity was found for 2-isonicotinoyl-N-(2,4,6-trichlorophenyl)hydrazinecarboxamide (MIC = 4 μM). In silico modelling on the enoyl-acyl carrier protein reductase InhA confirmed that longer alkyl substituents are advantageous for the interactions and affinity to InhA. Most of the hydrazinecarboxamides, especially those derived from 4-alkylanilines, exhibited significant activity against INH-resistant nontuberculous mycobacteria. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Interaction Between Different Extracts of Hypericum perforatum L. from Serbia and Pentobarbital, Diazepam and Paracetamol
Molecules 2014, 19(4), 3869-3882; doi:10.3390/molecules19043869
Received: 20 December 2013 / Revised: 16 March 2014 / Accepted: 19 March 2014 / Published: 28 March 2014
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Abstract
Herb-drug interactions are an important safety concern and this study was conducted regarding the interaction between the natural top-selling antidepressant remedy Hypericum perforatum (Hypericaceae) and conventional drugs. This study examined the influence of acute pretreatment with different extracts of Hypericum perforatum from [...] Read more.
Herb-drug interactions are an important safety concern and this study was conducted regarding the interaction between the natural top-selling antidepressant remedy Hypericum perforatum (Hypericaceae) and conventional drugs. This study examined the influence of acute pretreatment with different extracts of Hypericum perforatum from Serbia on pentobarbital-induced sleeping time, impairment of motor coordination caused by diazepam and paracetamol pharmacokinetics in mice. Ethanolic extract, aqueous extract, infusion, tablet and capsule of Hypericum perforatum were used in this experiment. The profile of Hypericum perforatum extracts as well as paracetamol plasma concentration was determined using RP-HPLC analysis. By quantitative HPLC analysis of active principles, it has been proven that Hypericum perforatum ethanolic extract has the largest content of naphtodianthrones: hypericin (57.77 µg/mL) and pseudohypericin (155.38 µg/mL). Pretreatment with ethanolic extract of Hypericum perforatum potentiated the hypnotic effect of pentobarbital and impairment of motor coordination caused by diazepam to the greatest extent and also increased paracetamol plasma concentration in comparison to the control group. These results were in correlation with naphtodianthrone concentrations. The obtained results have shown a considerable influence of Hypericum perforatum on pentobarbital and diazepam pharmacodynamics and paracetamol pharmacokinetics. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Structures of Two New Flavonoids and Effects of Licorice Phenolics on Vancomycin-Resistant Enterococcus Species
Molecules 2014, 19(4), 3883-3897; doi:10.3390/molecules19043883
Received: 28 February 2014 / Revised: 17 March 2014 / Accepted: 21 March 2014 / Published: 28 March 2014
Cited by 5 | PDF Full-text (314 KB) | HTML Full-text | XML Full-text
Abstract
Since our previous study revealed that several licorice phenolics have antibacterial effects on methicillin-resistant Staphylococcus aureus (MRSA), and suppressive effects on the oxacillin resistance of MRSA, we further investigated effectiveness of licorice constituents on vancomycin-resistant Enterococcus (VRE) bacteria, and purified 32 phenolic [...] Read more.
Since our previous study revealed that several licorice phenolics have antibacterial effects on methicillin-resistant Staphylococcus aureus (MRSA), and suppressive effects on the oxacillin resistance of MRSA, we further investigated effectiveness of licorice constituents on vancomycin-resistant Enterococcus (VRE) bacteria, and purified 32 phenolic compounds. Two flavonoids among them were characterized structurally, and identified their structures as demethylglycyrol (31) and 5,7-di-O-methylluteone (32), respectively. Examination of antibacterial effects of licorice phenolics showed that 3-arylcoumarins such as licoarylcoumarin (9) and glycycoumarin (26), and 2-arylcoumarones such as gancaonin I (17), have moderate to potent antibacterial effects on the VRE strains used in this study. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Further Mulinane and Azorellane Diterpenoids Isolated from Mulinum crassifolium and Azorella compacta
Molecules 2014, 19(4), 3898-3908; doi:10.3390/molecules19043898
Received: 3 March 2014 / Revised: 19 March 2014 / Accepted: 21 March 2014 / Published: 28 March 2014
Cited by 4 | PDF Full-text (873 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The new mulinane diterpenoids 1 and 2 were isolated from the EtOAc extract of Mulinum crassifolium, while the rearranged mulinane 5, which was isolated for the first time from a natural source, was isolated from Azorella compacta. Compounds 1 [...] Read more.
The new mulinane diterpenoids 1 and 2 were isolated from the EtOAc extract of Mulinum crassifolium, while the rearranged mulinane 5, which was isolated for the first time from a natural source, was isolated from Azorella compacta. Compounds 12 were prepared by semi-synthesis thorough acetylation of the diterpene 17-acetoxymulinic acid (3). A mechanism of reaction was proposed, while the structures of the new compounds were elucidated on the basis of comprehensive spectroscopic analysis and computational methods. Full article
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Open AccessArticle Comparison of Physicochemical Properties and Immunomodulatory Activity of Polysaccharides from Fresh and Dried Litchi Pulp
Molecules 2014, 19(4), 3909-3925; doi:10.3390/molecules19043909
Received: 17 February 2014 / Revised: 20 March 2014 / Accepted: 21 March 2014 / Published: 31 March 2014
Cited by 9 | PDF Full-text (412 KB) | HTML Full-text | XML Full-text
Abstract
Drying is commonly used for preservation and processing of litchi. However, its polysaccharide structure may be altered by the drying process, resulting in biological activity changes. Polysaccharides from fresh and dried litchi pulp (denoted as LPF and LPD, respectively) were isolated, investigated [...] Read more.
Drying is commonly used for preservation and processing of litchi. However, its polysaccharide structure may be altered by the drying process, resulting in biological activity changes. Polysaccharides from fresh and dried litchi pulp (denoted as LPF and LPD, respectively) were isolated, investigated by GC-MS, GPC and UV/IR spectrum analysis and their antitumor and immunomodulatory activities were evaluated in vitro. LPD, the molecular weight of which was lower than that of LPF, contained more protein, uronic acid, arabinose, galactose and xylose. Compared with LPF, LPD exhibited a higher inhibitory effect on the proliferation of HepG2, Hela and A549 cells from 50–750 μg/mL. LPD was also a better stimulator of spleen lymphocyte proliferation, NK cells cytotoxicity and macrophage phagocytosis from 50–400 μg/mL. In summary, drying could change the physicochemical properties and enhance the bioactivity of polysaccharides from litchi pulp. This finding is supported by the fact that dried litchi pulps are used in Traditional Chinese Medicine. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Angelica sinensis Improves Exercise Performance and Protects against Physical Fatigue in Trained Mice
Molecules 2014, 19(4), 3926-3939; doi:10.3390/molecules19043926
Received: 9 February 2014 / Revised: 3 March 2014 / Accepted: 17 March 2014 / Published: 31 March 2014
Cited by 2 | PDF Full-text (894 KB) | HTML Full-text | XML Full-text
Abstract
Angelica sinensis (AS) is a well-known medicinal herb and food material with antioxidative and multifunctional pharmacological activities. However, we lack evidence of the effect of AS on exercise performance and physical fatigue. We aimed to evaluate the potential beneficial effect of AS [...] Read more.
Angelica sinensis (AS) is a well-known medicinal herb and food material with antioxidative and multifunctional pharmacological activities. However, we lack evidence of the effect of AS on exercise performance and physical fatigue. We aimed to evaluate the potential beneficial effect of AS on ergogenic and anti-fatigue functions after physiological challenge. Male ICR strain mice were randomly assigned to four groups (n = 10 per group) for treatment: (1) sedentary control and vehicle treatment (vehicle control); (2) exercise training with vehicle treatment (exercise control); (3) exercise training with AS treatment at 0.41 g/kg/day (Ex-AS1); and (4) 2.05 g/kg/day (Ex-AS5); both the vehicle and AS were orally administered for 6 weeks. Exercise performance and anti-fatigue function were evaluated by forelimb grip strength, exhaustive swimming time, and levels of serum lactate, ammonia, glucose, and creatine kinase (CK) after a 15-min swimming exercise. Trend analysis revealed that AS treatments significantly increased endurance swimming time and blood glucose level, and decreased serum lactate, ammonia and CK levels. Liver and muscle glycogen contents were higher for Ex-AS1 and Ex-AS5 groups than the exercise control. Therefore, AS supplementation improved exercise performance and had anti-fatigue properties in mice and may be an effective ergogenic aid in exercise training. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Water Extract of Acer tegmentosum Reduces Bone Destruction by Inhibiting Osteoclast Differentiation and Function
Molecules 2014, 19(4), 3940-3954; doi:10.3390/molecules19043940
Received: 8 January 2014 / Revised: 24 March 2014 / Accepted: 25 March 2014 / Published: 1 April 2014
Cited by 6 | PDF Full-text (947 KB) | HTML Full-text | XML Full-text
Abstract
The stem of Acer tegmentosum has been widely used in Korea for the treatment of hepatic disorders. In this study, we investigated the bone protective effect of water extract of the stem of Acer tegmentosum (WEAT). We found that WEAT inhibits osteoclast [...] Read more.
The stem of Acer tegmentosum has been widely used in Korea for the treatment of hepatic disorders. In this study, we investigated the bone protective effect of water extract of the stem of Acer tegmentosum (WEAT). We found that WEAT inhibits osteoclast differentiation induced by receptor activator of nuclear factor-κB ligand (RANKL), an essential cytokine for osteoclast differentiation. In osteoclast precursor cells, WEAT inhibited RANKL-induced activation of JNK, NF-κB, and cAMP response element-binding protein, leading to suppression of the induction of c-Fos and nuclear factor of activated T cells cytoplasmic 1, key transcription factors for osteoclast differentiation. In addition, WEAT inhibited bone resorbing activity of mature osteoclasts. Furthermore, the oral administration of WEAT reduced RANKL-induced bone resorption and trabecular bone loss in mice. Taken together, our study demonstrates that WEAT possesses a protective effect on bone destruction by inhibiting osteoclast differentiation and function. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Cinchona Alkaloid Derivative-Catalyzed Enantioselective Synthesis via a Mannich-Type Reaction and Antifungal Activity of β-Amino Esters Bearing Benzoheterocycle Moieties
Molecules 2014, 19(4), 3955-3972; doi:10.3390/molecules19043955
Received: 7 March 2014 / Revised: 19 March 2014 / Accepted: 21 March 2014 / Published: 1 April 2014
Cited by 3 | PDF Full-text (359 KB) | HTML Full-text | XML Full-text
Abstract
An efficient synthesis of highly functionalized chiral β-amino ester derivatives containing benzothiophene and benzothiazole moieties is developed by a Mannich-type reaction using a cinchona alkaloid-derived thiourea catalyst. The desired products were obtained in good yields and high enantioselectivities (~86% yield, >99% ee) [...] Read more.
An efficient synthesis of highly functionalized chiral β-amino ester derivatives containing benzothiophene and benzothiazole moieties is developed by a Mannich-type reaction using a cinchona alkaloid-derived thiourea catalyst. The desired products were obtained in good yields and high enantioselectivities (~86% yield, >99% ee) using to the optimized reaction conditions. The synthesized compounds were characterized by 1H-NMR, 13C-NMR, IR, and HREI-MS analyses. The bioassays identified that compound 5dr has excellent antifungal activity, with a 60.53% inhibition rate against F. oxysporum, higher than that of the commercial agricultural fungicide hymexazol, whose inhibition rate was 56.12%. Full article
(This article belongs to the Section Organic Synthesis)
Open AccessArticle First Chemical Evaluation and Toxicity of Casinga-cheirosa to Balb-c Male Mice
Molecules 2014, 19(4), 3973-3987; doi:10.3390/molecules19043973
Received: 10 February 2014 / Revised: 27 February 2014 / Accepted: 13 March 2014 / Published: 2 April 2014
Cited by 2 | PDF Full-text (284 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Laetia suaveolens, known as “casinga-cheirosa”, crude extract EB719 has previously shown cytotoxic activity against prostate cancer and squamous cell carcinoma. For the first time, seven molecules were isolated from its apolar—α-tocopherol (1) and sitosterol (2)—and polar—3-O [...] Read more.
Laetia suaveolens, known as “casinga-cheirosa”, crude extract EB719 has previously shown cytotoxic activity against prostate cancer and squamous cell carcinoma. For the first time, seven molecules were isolated from its apolar—α-tocopherol (1) and sitosterol (2)—and polar—3-O-caffeoylquinic acid (3), 4-O-caffeoylquinic acid (4), 5-O-feruloylquinic acid (5), hyperoside (6), and isoquercitrin (7)—fractions. Acute toxicity was determined in a two-stage experiment: (1) a reduced number of Balb-c male mice received 5000 mg/kg of EB719 to allow evaluation of general activity and other 27 parameters, plus death, up to the establishment of non-lethal dose (NLD), as well as lethal dose 50% (LD50); (2) NLD was administered and diazepam introduced as reference drug. EB719 showed LD50 = 178.0 mg/kg, and NLD 156.3 mg/kg. In stage one EB719 did not influence general activity, but provoked impairment in grasp reflexes, tail squeeze and breathing; piloerection and cyanosis were increased. In stage two, alterations occurred in auricular reflex, piloerection and breathing after diazepam administration, but not in response to EB719. Intestinal hemorrhage caused by local bleeding was observed after necropsy, and may be the main cause of animals’ death other than a systemic effect of the extract. Although the isolated compounds are biologically and pharmacologically active in both men and animal systems, it is premature to relate their occurrence in EB719 to the observed intestine hemorrhage in mice. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Camalexin-Induced Apoptosis in Prostate Cancer Cells Involves Alterations of Expression and Activity of Lysosomal Protease Cathepsin D
Molecules 2014, 19(4), 3988-4005; doi:10.3390/molecules19043988
Received: 7 January 2014 / Revised: 5 March 2014 / Accepted: 5 March 2014 / Published: 2 April 2014
Cited by 5 | PDF Full-text (2117 KB) | HTML Full-text | XML Full-text
Abstract
Camalexin, the phytoalexin produced in the model plant Arabidopsis thaliana, possesses antiproliferative and cancer chemopreventive effects. We have demonstrated that the cytostatic/cytotoxic effects of camalexin on several prostate cancer (PCa) cells are due to oxidative stress. Lysosomes are vulnerable organelles to [...] Read more.
Camalexin, the phytoalexin produced in the model plant Arabidopsis thaliana, possesses antiproliferative and cancer chemopreventive effects. We have demonstrated that the cytostatic/cytotoxic effects of camalexin on several prostate cancer (PCa) cells are due to oxidative stress. Lysosomes are vulnerable organelles to Reactive Oxygen Species (ROS)-induced injuries, with the potential to initiate and or facilitate apoptosis subsequent to release of proteases such as cathepsin D (CD) into the cytosol. We therefore hypothesized that camalexin reduces cell viability in PCa cells via alterations in expression and activity of CD. Cell viability was evaluated by MTS cell proliferation assay in LNCaP and ARCaP Epithelial (E) cells, and their respective aggressive sublines C4-2 and ARCaP Mesenchymal (M) cells, whereby the more aggressive PCa cells (C4-2 and ARCaPM) displayed greater sensitivity to camalexin treatments than the lesser aggressive cells (LNCaP and ARCaPE). Immunocytochemical analysis revealed CD relocalization from the lysosome to the cytosol subsequent to camalexin treatments, which was associated with increased protein expression of mature CD; p53, a transcriptional activator of CD; BAX, a downstream effector of CD, and cleaved PARP, a hallmark for apoptosis. Therefore, camalexin reduces cell viability via CD and may present as a novel therapeutic agent for treatment of metastatic prostate cancer cells. Full article
Open AccessArticle PBDE: Structure-Activity Studies for the Inhibition of Hepatitis C Virus NS3 Helicase
Molecules 2014, 19(4), 4006-4020; doi:10.3390/molecules19044006
Received: 17 January 2014 / Revised: 5 March 2014 / Accepted: 13 March 2014 / Published: 2 April 2014
Cited by 4 | PDF Full-text (938 KB) | HTML Full-text | XML Full-text
Abstract
The helicase portion of the hepatitis C virus nonstructural protein 3 (NS3) is considered one of the most validated targets for developing direct acting antiviral agents. We isolated polybrominated diphenyl ether (PBDE) 1 from a marine sponge as an NS3 helicase inhibitor. [...] Read more.
The helicase portion of the hepatitis C virus nonstructural protein 3 (NS3) is considered one of the most validated targets for developing direct acting antiviral agents. We isolated polybrominated diphenyl ether (PBDE) 1 from a marine sponge as an NS3 helicase inhibitor. In this study, we evaluated the inhibitory effects of PBDE (1) on the essential activities of NS3 protein such as RNA helicase, ATPase, and RNA binding activities. The structure-activity relationship analysis of PBDE (1) against the HCV ATPase revealed that the biphenyl ring, bromine, and phenolic hydroxyl group on the benzene backbone might be a basic scaffold for the inhibitory potency. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Computational Redesign of Bacterial Biotin Carboxylase Inhibitors Using Structure-Based Virtual Screening of Combinatorial Libraries
Molecules 2014, 19(4), 4021-4045; doi:10.3390/molecules19044021
Received: 21 February 2014 / Revised: 19 March 2014 / Accepted: 25 March 2014 / Published: 2 April 2014
Cited by 4 | PDF Full-text (4483 KB) | HTML Full-text | XML Full-text
Abstract
As the spread of antibiotic resistant bacteria steadily increases, there is an urgent need for new antibacterial agents. Because fatty acid synthesis is only used for membrane biogenesis in bacteria, the enzymes in this pathway are attractive targets for antibacterial agent development. [...] Read more.
As the spread of antibiotic resistant bacteria steadily increases, there is an urgent need for new antibacterial agents. Because fatty acid synthesis is only used for membrane biogenesis in bacteria, the enzymes in this pathway are attractive targets for antibacterial agent development. Acetyl-CoA carboxylase catalyzes the committed and regulated step in fatty acid synthesis. In bacteria, the enzyme is composed of three distinct protein components: biotin carboxylase, biotin carboxyl carrier protein, and carboxyltransferase. Fragment-based screening revealed that amino-oxazole inhibits biotin carboxylase activity and also exhibits antibacterial activity against Gram-negative organisms. In this report, we redesigned previously identified lead inhibitors to expand the spectrum of bacteria sensitive to the amino-oxazole derivatives by including Gram-positive species. Using 9,411 small organic building blocks, we constructed a diverse combinatorial library of 1.2 × 108 amino-oxazole derivatives. A subset of 9 × 106 of these compounds were subjected to structure-based virtual screening against seven biotin carboxylase isoforms using similarity-based docking by eSimDock. Potentially broad-spectrum antibiotic candidates were selected based on the consensus ranking by several scoring functions including non-linear statistical models implemented in eSimDock and traditional molecular mechanics force fields. The analysis of binding poses of the top-ranked compounds docked to biotin carboxylase isoforms suggests that: (1) binding of the amino-oxazole anchor is stabilized by a network of hydrogen bonds to residues 201, 202 and 204; (2) halogenated aromatic moieties attached to the amino-oxazole scaffold enhance interactions with a hydrophobic pocket formed by residues 157, 169, 171 and 203; and (3) larger substituents reach deeper into the binding pocket to form additional hydrogen bonds with the side chains of residues 209 and 233. These structural insights into drug-biotin carboxylase interactions will be tested experimentally in in vitro and in vivo systems to increase the potency of amino-oxazole inhibitors towards both Gram-negative as well as Gram-positive species. Full article
(This article belongs to the Special Issue In-Silico Drug Design and In-Silico Screening)
Open AccessArticle Chemical Composition and Biological Activities of Gerbera anandria
Molecules 2014, 19(4), 4046-4057; doi:10.3390/molecules19044046
Received: 18 January 2014 / Revised: 17 March 2014 / Accepted: 25 March 2014 / Published: 2 April 2014
Cited by 2 | PDF Full-text (303 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Gerbera anandria (Compositae) was extracted with 75% ethanol and the residue was fractionated using light petroleum, chloroform and ethyl acetate. The constituents of the extracts were separated by column chromatography employing solvents of different polarity. Column chromatography of the light petroleum fraction [...] Read more.
Gerbera anandria (Compositae) was extracted with 75% ethanol and the residue was fractionated using light petroleum, chloroform and ethyl acetate. The constituents of the extracts were separated by column chromatography employing solvents of different polarity. Column chromatography of the light petroleum fraction resulted in the isolation of methyl hexadecanoate, while the chloroform fraction afforded xanthotoxin, 2-hydroxy-6-methylbenzoic acid, 7-hydroxy-1(3H)-isobenzofuranone, a mixture of β-sitosterol and stigmasterol, and 8-methoxysmyrindiol and the ethyl acetate fraction gave gerberinside, apigenin-7-O-β-d-glucopyranoside and quercetin. A new coumarin, 8-methoxysmyrindiol, was found. The chemical structures of the isolated compounds were established by MS and NMR (HSQC, HMBC). Free radical scavenging and cytotoxic activities of crude extracts and 8-methoxysmyrindiol were further investigated. The ethyl acetate phase exerted the strongest DPPH free radical scavenging activity in comparison to the other fractions. The coumarin 8-methoxysmyrindiol demonstrated cytotoxicity against multiple human cancer cell lines, with the highest potency in HepG2 cells. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Determination of Bioactive Components in Chinese Herbal Formulae and Pharmacokinetics of Rhein in Rats by UPLC-MS/MS
Molecules 2014, 19(4), 4058-4075; doi:10.3390/molecules19044058
Received: 17 February 2014 / Revised: 22 March 2014 / Accepted: 27 March 2014 / Published: 2 April 2014
Cited by 8 | PDF Full-text (800 KB) | HTML Full-text | XML Full-text
Abstract
Rhein (4,5-dihydroxy-9,10-dioxoanthracene-2-carboxylic acid, cassic acid) is a pharmacological active component found in Rheum palmatum L. the major herb of San-Huang-Xie-Xin-Tang (SHXXT), a medicinal herbal product used as a remedy for constipation. Here we have determined multiple bioactive components in SHXXT and investigated [...] Read more.
Rhein (4,5-dihydroxy-9,10-dioxoanthracene-2-carboxylic acid, cassic acid) is a pharmacological active component found in Rheum palmatum L. the major herb of San-Huang-Xie-Xin-Tang (SHXXT), a medicinal herbal product used as a remedy for constipation. Here we have determined multiple bioactive components in SHXXT and investigated the comparative pharmacokinetics of rhein in rats. A sensitive and specific method combining liquid chromatography with electrospray ionization tandem mass spectrometry has been developed and validated to simultaneously quantify six active compounds in the pharmaceutical herbal product SHXXT to further study their pharmacokinetics in rats. Multiple reaction monitoring (MRM) was employed for quantification with switching electrospray ion source polarity between positive and negative modes in a single run. There were no significant matrix effects in the quantitative analysis and the mean recovery for rhein in rat plasma was 91.6% ± 3.4%. The pharmacokinetic data of rhein demonstrate that the herbal formulae or the single herbal extract provide significantly higher absorption rate than the pure compound. This phenomenon suggests that the other herbal ingredients of SHXXT and rhubarb extract significantly enhance the absorption of rhein in rats. In conclusion, the herbal formulae (SHXXT) are more efficient than the single herb (rhubarb) or the pure compound (rhein) in rhein absorption. Full article
Open AccessCommunication A One-Step Microwave-Assisted Synthetic Method for an O/S-Chemoselective Route to Derivatives of the First Adenosine A3 PET Radiotracer
Molecules 2014, 19(4), 4076-4082; doi:10.3390/molecules19044076
Received: 28 January 2014 / Revised: 21 March 2014 / Accepted: 24 March 2014 / Published: 2 April 2014
PDF Full-text (202 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The synthesis of reference standards and expected in vivo metabolites of the first adenosine A3 PET radiotracer [18F]FE@SUPPY ([18F]fluoroethyl 4,6-diethyl-5-[(ethyl-sulfanyl)carbonyl]-2-phenylpyridine-3-carboxylate) was achieved by using a straightforward microwave assisted alkylation method, which allowed O/S-chemoselective alkylation of the starting material [...] Read more.
The synthesis of reference standards and expected in vivo metabolites of the first adenosine A3 PET radiotracer [18F]FE@SUPPY ([18F]fluoroethyl 4,6-diethyl-5-[(ethyl-sulfanyl)carbonyl]-2-phenylpyridine-3-carboxylate) was achieved by using a straightforward microwave assisted alkylation method, which allowed O/S-chemoselective alkylation of the starting material 1 to give each target compound 28 in a single step. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Simultaneous Determination of Original, Degraded Ginsenosides and Aglycones by Ultra High Performance Liquid Chromatography Coupled with Quadrupole Time-of-Flight Mass Spectrometry for Quantitative Evaluation of Du-Shen-Tang, the Decoction of Ginseng
Molecules 2014, 19(4), 4083-4104; doi:10.3390/molecules19044083
Received: 21 February 2014 / Revised: 21 March 2014 / Accepted: 24 March 2014 / Published: 2 April 2014
Cited by 4 | PDF Full-text (364 KB) | HTML Full-text | XML Full-text
Abstract
In the present study, an ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) method for simultaneous determination of eleven original, fourteen degraded ginsenosides and five aglycones was developed and validated to quantitatively evaluate the transformation of ginsenosides during preparation [...] Read more.
In the present study, an ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) method for simultaneous determination of eleven original, fourteen degraded ginsenosides and five aglycones was developed and validated to quantitatively evaluate the transformation of ginsenosides during preparation of Du-Shen-Tang, the decoction of ginseng. Both positive and negative modes as well as the step wave ion transfer optics technology were used to increase the detection sensitivity of QTOF-MS. The extracting ion mode based on the quasi-molecular ions, molecular ions and fragment ions characteristic to each analyte was used to increase the selectivity for quantitative analysis. Under the optimized UHPLC and QTOF-MS conditions, the 30 analytes with different polarities were separated (except for Re and Rg1) within 26 min. The developed method was applied for the quantitative comparison of Du-Shen-Tang and its raw materials derived from Asian ginseng (ASG) and American ginseng (AMG), respectively. It was found that the contents of the original ginsenosides decreased from 26,053.09 to 19,393.29 μg/g or 45,027.72 to 41,865.39 μg/g, whereas the degraded ginsenosides and aglycones increased from 159.72 to 685.37 μg/g or 676.54 to 1,502.26 μg/g in Du-Shen-Tang samples of ASG or AMG when compared with their raw materials, indicating that decocting could dramatically increase the proportion of the less polar degraded ginsenosides in Du-Shen-Tang. Whether these changed proportions of different polar ginsenosides could affect the bioactivities of the decoctions and their raw materials derived from ASG and AMG deserves further investigation. Full article
Open AccessArticle Fluorescent Probes for Insect Ryanodine Receptors: Candidate Anthranilic Diamides
Molecules 2014, 19(4), 4105-4114; doi:10.3390/molecules19044105
Received: 16 January 2014 / Revised: 13 March 2014 / Accepted: 21 March 2014 / Published: 2 April 2014
Cited by 3 | PDF Full-text (632 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Diamide insecticides with high efficacy against pests and good environmental safety are broadly applied in crop protection. They act at a poorly-defined site in the very complex ryanodine (Ry) receptor (RyR) potentially accessible to a fluorescent probe. Two N-propynyl analogs of [...] Read more.
Diamide insecticides with high efficacy against pests and good environmental safety are broadly applied in crop protection. They act at a poorly-defined site in the very complex ryanodine (Ry) receptor (RyR) potentially accessible to a fluorescent probe. Two N-propynyl analogs of the major anthranilic diamide insecticides chlorantraniliprole (Chlo) and cyantraniliprole (Cyan) were accordingly synthesized and converted into two fluorescent ligands by click reaction coupling with 3-azido-7-hydroxy-2H-chromen-2-one. The new diamide analogs and fluorescent ligands were shown to be nearly as potent as Chlo and Cyan in inhibition of [3H]Chlo binding and stimulation of [3H]Ry binding in house fly thoracic muscle RyR. Although the newly synthesized compounds had only moderate activity in insect larvicidal activity assays, their high in vitro potency in a validated insect RyR binding assay encourages further development of fluorescent probes for insect RyRs. Full article
Open AccessArticle Chemo-Enzymatic Synthesis of Silybin and 2,3-Dehydrosilybin Dimers
Molecules 2014, 19(4), 4115-4134; doi:10.3390/molecules19044115
Received: 12 February 2014 / Revised: 24 March 2014 / Accepted: 27 March 2014 / Published: 2 April 2014
Cited by 7 | PDF Full-text (1001 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Divalent or multivalent molecules often show enhanced biological activity relative to the simple monomeric units. Here we present enzymatically and chemically prepared dimers of the flavonolignans silybin and 2,3-dehydrosilybin. Their electrochemical behavior was studied by in situ and ex situ square wave [...] Read more.
Divalent or multivalent molecules often show enhanced biological activity relative to the simple monomeric units. Here we present enzymatically and chemically prepared dimers of the flavonolignans silybin and 2,3-dehydrosilybin. Their electrochemical behavior was studied by in situ and ex situ square wave voltammetry. The oxidation of monomers and dimers was similar, but adsorption onto the electrode and cell surfaces was different. A 1,1-diphenyl-2-picrylhydrazyl (DPPH) and an inhibition of microsomal lipoperoxidation assay were performed with same trend of results for silybin and 2,3-dehydrosilybin dimers. Silybin dimer showed better activity than the monomer, while on the contrary 2,3-dehydrosilybin dimer presented weaker antioxidant/antilipoperoxidant activity than its monomer. Cytotoxicity was evaluated on human umbilical vein endothelial cells, normal human adult keratinocytes, mouse fibroblasts (BALB/c 3T3) and human liver hepatocellular carcinoma cell line (HepG2). Silybin dimer was more cytotoxic than the parent compound and in the case of 2,3-dehydrosilybin its dimer showed weaker cytotoxicity than the monomer. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Turn-on Type Chemical Sensing of Vitamin K4 by Fluorene Dendrimers with Naphthalene Segments
Molecules 2014, 19(4), 4135-4144; doi:10.3390/molecules19044135
Received: 7 March 2014 / Revised: 27 March 2014 / Accepted: 28 March 2014 / Published: 2 April 2014
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Abstract
G1 and G2 fluorene dendrimers with naphthalene termini were synthesized as a fluorescence turn-on type chemical sensor for vitamin K4. The fluorene dendrimers were prepared by Williamson ether reaction between the fluorene core with dihydroxy groups and dendritic naphthalene segments with methylene [...] Read more.
G1 and G2 fluorene dendrimers with naphthalene termini were synthesized as a fluorescence turn-on type chemical sensor for vitamin K4. The fluorene dendrimers were prepared by Williamson ether reaction between the fluorene core with dihydroxy groups and dendritic naphthalene segments with methylene chloride by a convergent method. We investigated the relationship between the dendrimer generation and vitamin K4 recognition of fluorene dendrimer with naphthalene termini in CHCl3. Addition of vitamin K4 enhanced the fluorescence intensity of the fluorene dendrimer. Especially, the G2 fluorene dendrimer was found to be an effective chemical sensor for vitamin K4 and better than the G1 fluorene dendrimer. Full article
(This article belongs to the Special Issue Fluorescent Probes)
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Open AccessArticle Optical Absorption of the Antitrypanocidal Drug Benznidazole inWater
Molecules 2014, 19(4), 4145-4156; doi:10.3390/molecules19044145
Received: 26 January 2014 / Revised: 24 February 2014 / Accepted: 14 March 2014 / Published: 2 April 2014
Cited by 1 | PDF Full-text (2814 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
UV-vis optical absorption spectra of the antitrypanocidal drug benznidazole solvated in water were measured for various concentrations. The spectra show a prominent peak around 3.80 eV, while deconvolution of the UV-vis optical absorption spectra revealed six bands centered at 3.60, 3.83, 4.15, [...] Read more.
UV-vis optical absorption spectra of the antitrypanocidal drug benznidazole solvated in water were measured for various concentrations. The spectra show a prominent peak around 3.80 eV, while deconvolution of the UV-vis optical absorption spectra revealed six bands centered at 3.60, 3.83, 4.15, 4.99, 5.60, and 5.76 eV. Benznidazole electronic transitions were obtained after density functional theory (DFT) calculations within the polarized continuum (PCM) model for water solvation. Molecular geometry optimizations were carried out, and the measured absorption peaks were related to specific molecular orbital transitions obtained within the time dependent DFT (TD-DFT) with excellent agreement between theory and experiment. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Bondonic Effects in Group-IV Honeycomb Nanoribbons with Stone-Wales Topological Defects
Molecules 2014, 19(4), 4157-4188; doi:10.3390/molecules19044157
Received: 23 February 2014 / Revised: 26 March 2014 / Accepted: 27 March 2014 / Published: 3 April 2014
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Abstract
This work advances the modeling of bondonic effects on graphenic and honeycomb structures, with an original two-fold generalization: (i) by employing the fourth order path integral bondonic formalism in considering the high order derivatives of the Wiener topological potential of those 1D [...] Read more.
This work advances the modeling of bondonic effects on graphenic and honeycomb structures, with an original two-fold generalization: (i) by employing the fourth order path integral bondonic formalism in considering the high order derivatives of the Wiener topological potential of those 1D systems; and (ii) by modeling a class of honeycomb defective structures starting from graphene, the carbon-based reference case, and then generalizing the treatment to Si (silicene), Ge (germanene), Sn (stannene) by using the fermionic two-degenerate statistical states function in terms of electronegativity. The honeycomb nanostructures present η-sized Stone-Wales topological defects, the isomeric dislocation dipoles originally called by authors Stone-Wales wave or SWw. For these defective nanoribbons the bondonic formalism foresees a specific phase-transition whose critical behavior shows typical bondonic fast critical time and bonding energies. The quantum transition of the ideal-to-defect structural transformations is fully described by computing the caloric capacities for nanostructures triggered by η-sized topological isomerisations. Present model may be easily applied to hetero-combinations of Group-IV elements like C-Si, C-Ge, C-Sn, Si-Ge, Si-Sn, Ge-Sn. Full article
(This article belongs to the Special Issue Quantum Information in Molecular Structures and Nanosystems)
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Open AccessArticle Agaricus Blazei Hot Water Extract Shows Anti Quorum Sensing Activity in the Nosocomial Human Pathogen Pseudomonas Aeruginosa
Molecules 2014, 19(4), 4189-4199; doi:10.3390/molecules19044189
Received: 18 February 2014 / Revised: 24 March 2014 / Accepted: 28 March 2014 / Published: 3 April 2014
Cited by 7 | PDF Full-text (300 KB) | HTML Full-text | XML Full-text
Abstract
The edible mushroom Agaricus blazei Murill is known to induce protective immunomodulatory action against a variety of infectious diseases. In the present study we report potential anti-quorum sensing properties of A. blazei hot water extract. Quorum sensing (QS) plays an important role [...] Read more.
The edible mushroom Agaricus blazei Murill is known to induce protective immunomodulatory action against a variety of infectious diseases. In the present study we report potential anti-quorum sensing properties of A. blazei hot water extract. Quorum sensing (QS) plays an important role in virulence, biofilm formation and survival of many pathogenic bacteria, including the Gram negative Pseudomonas aeruginosa, and is considered as a novel and promising target for anti-infectious agents. In this study, the effect of the sub-MICs of Agaricus blazei water extract on QS regulated virulence factors and biofilm formation was evaluated against P. aeruginosa PAO1. Sub-MIC concentrations of the extract which did not kill P. aeruginosa nor inhibited its growth, demonstrated a statistically significant reduction of virulence factors of P. aeruginosa, such as pyocyanin production, twitching and swimming motility. The biofilm forming capability of P. aeruginosa was also reduced in a concentration-dependent manner at sub-MIC values. Water extract of A. blazei is a promising source of antiquorum sensing and antibacterial compounds. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Antiprotozoal Activities of Millettia richardiana (Fabaceae) from Madagascar
Molecules 2014, 19(4), 4200-4211; doi:10.3390/molecules19044200
Received: 21 January 2014 / Revised: 18 March 2014 / Accepted: 19 March 2014 / Published: 3 April 2014
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Abstract
With at least 60% of the Millettia species (Fabaceae) being in medicinal use, we found it relevant to assess the potential antiprotozoal and antifungal activities of Millettia richardiana. Water and methanol crude extracts of the stem barks from M. richardiana and the [...] Read more.
With at least 60% of the Millettia species (Fabaceae) being in medicinal use, we found it relevant to assess the potential antiprotozoal and antifungal activities of Millettia richardiana. Water and methanol crude extracts of the stem barks from M. richardiana and the six fractions resulting from the fractionation of the methanol extract were tested. The dichloromethane extracted fraction showed the best in vitro antiprotozoal activities (IC50 = 5.8 μg/mL against Plasmodium falciparum, 11.8 μg/mL against Leishmania donovani and 12.8 μg/mL against Trypanosoma brucei brucei) as well as low cytotoxicity on several cell lines. The phytochemical analysis showed this selected fraction to be rich in terpenoids and alkaloids, which could explain its antiparasitic activity. A phytochemical study revealed the presence of lonchocarpenin, betulinic acid, β-amyrin, lupeol, palmitic acid, linoleic acid and stearic acid, among which betulinic acid and lupeol could be the compounds responsible of these antiprotozoal activities. By contrast, neither the crude extracts nor the fractions showed antifungal activity against Candida. These results confirm the importance of the genus Millettia in Malagasy ethnomedicine, its potential use in antiparasitic therapy, and the interest of developing a sustainable exploitation of this plant. Moreover, both molecules betulinic acid and lupeol appeared as very relevant molecules for their antiprotozoal properties. Full article
Open AccessArticle Synthesis, Spectroscopic and Theoretical Studies of New Quaternary N,N-Dimethyl-3-phthalimidopropylammonium Conjugates of Sterols and Bile Acids
Molecules 2014, 19(4), 4212-4233; doi:10.3390/molecules19044212
Received: 12 February 2014 / Revised: 19 March 2014 / Accepted: 21 March 2014 / Published: 3 April 2014
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Abstract
New quaternary 3-phthalimidopropylammonium conjugates of steroids were obtained by reaction of sterols (ergosterol, cholesterol, cholestanol) and bile acids (lithocholic, deoxycholic, cholic) with bromoacetic acid bromide to give sterol 3β-bromoacetates and bile acid 3α-bromoacetates, respectively. These intermediates were subjected to nuclephilic substitution with [...] Read more.
New quaternary 3-phthalimidopropylammonium conjugates of steroids were obtained by reaction of sterols (ergosterol, cholesterol, cholestanol) and bile acids (lithocholic, deoxycholic, cholic) with bromoacetic acid bromide to give sterol 3β-bromoacetates and bile acid 3α-bromoacetates, respectively. These intermediates were subjected to nuclephilic substitution with N,N-dimethyl-3-phthalimidopropylamine to give the final quaternary ammonium salts. The structures of products were confirmed by spectral (1H-NMR, 13C-NMR, and FT-IR) analysis, mass spectrometry (ESI-MS, MALDI) as well as PM5 semiempirical methods and B3LYP ab initio methods. Estimation of the pharmacotherapeutic potential has been accomplished for synthesized compounds on the basis of Prediction of Activity Spectra for Substances (PASS). Full article
(This article belongs to the Section Organic Synthesis)
Open AccessArticle Antioxidant and Anticancer Constituents from the Leaves of Liriodendron tulipifera
Molecules 2014, 19(4), 4234-4245; doi:10.3390/molecules19044234
Received: 12 February 2014 / Revised: 24 March 2014 / Accepted: 26 March 2014 / Published: 3 April 2014
Cited by 8 | PDF Full-text (312 KB) | HTML Full-text | XML Full-text
Abstract
Sixteen compounds were extracted and purified from the leaves of Liriodendron tulipifera. These compounds include aporphines, oxoaporphine, coumarin, sesquiterpene lactone, benzenoids, cyclitol and steroids. (+)-Norstephalagine (2) (an aporphine) and scopoletin (8) (a coumarin) were isolated from Liriodendron [...] Read more.
Sixteen compounds were extracted and purified from the leaves of Liriodendron tulipifera. These compounds include aporphines, oxoaporphine, coumarin, sesquiterpene lactone, benzenoids, cyclitol and steroids. (+)-Norstephalagine (2) (an aporphine) and scopoletin (8) (a coumarin) were isolated from Liriodendron tulipifera leaves from the first time. The identified compounds were screened for their antiradical scavenging, metal chelating and ferric reducing power activities. The results have showed that these compounds have antioxidative activity. The study has also examined the chemopreventive property of the isolated compounds against human melanoma cells A375. The results shown that (−)-anonaine (1), (−)-liridinine (3), (+)-lirinidine (6), lysicamine (7) and epitulipinolide diepoxide (9) significantly inhibited the proliferation of melanoma cells. These results revealed that these compounds have antioxidative activity and chemopreventive activity in skin melanoma cells. Full article
(This article belongs to the Special Issue Natural Antioxidants and Ageing)
Open AccessCommunication Development of Multi-Functional Chelators Based on Sarcophagine Cages
Molecules 2014, 19(4), 4246-4255; doi:10.3390/molecules19044246
Received: 17 February 2014 / Revised: 30 March 2014 / Accepted: 1 April 2014 / Published: 3 April 2014
Cited by 7 | PDF Full-text (306 KB) | HTML Full-text | XML Full-text
Abstract A new class of multifunctionalized sarcophagine derivatives was synthesized for 64Cu chelation. The platform developed in this study could have broad applications in 64Cu-radiopharmaceuticals. Full article
(This article belongs to the Special Issue Bioconjugations)
Open AccessArticle Highly Efficient and Diastereoselective Synthesis of New Pyrazolylpyrrolizine and Pyrazolylpyrrolidine Derivates by a Three-Component Domino Process
Molecules 2014, 19(4), 4284-4300; doi:10.3390/molecules19044284
Received: 6 February 2014 / Revised: 27 March 2014 / Accepted: 28 March 2014 / Published: 4 April 2014
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Abstract Diastereoselective reactions between 4-formylpyrazoles, N-substituted maleimides and glycine derivates led to new series of pyrazolyldipyrrolo [3,4-a:3',4'-f]pyrrolizines and pyrazolylpyrrolo[3,4-c]pyrroles in good yields. The reactions proceeded by a domino process through azomethine ylides formed in situ via a 1,3-dipolar cycloaddition reaction. Full article
(This article belongs to the Section Organic Synthesis)
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Open AccessArticle Bioactive 30-Noroleanane Triterpenes from the Pericarps of Akebia trifoliata
Molecules 2014, 19(4), 4301-4312; doi:10.3390/molecules19044301
Received: 20 February 2014 / Revised: 27 March 2014 / Accepted: 28 March 2014 / Published: 4 April 2014
Cited by 4 | PDF Full-text (327 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Two new 30-noroleanane triterpenes, 2α,3β,20α-trihydroxy-30-norolean-12-en-28-oic acid (1), 2α,3β-dihydroxy-23-oxo-30-norolean-12,20(29)-dien-28-oic acid (2), were isolated from the pericarps of Akebia trifoliata, together with four known ones, 3β-akebonoic acid [...] Read more.
Two new 30-noroleanane triterpenes, 2α,3β,20α-trihydroxy-30-norolean-12-en-28-oic acid (1), 2α,3β-dihydroxy-23-oxo-30-norolean-12,20(29)-dien-28-oic acid (2), were isolated from the pericarps of Akebia trifoliata, together with four known ones, 3β-akebonoic acid (3), 2α,3β-dihydroxy-30-noroleana-12,20(29)-dien-28-oic acid (4), 3α-akebonoic acid (5) and quinatic acid (6). Their structures were established on the basis of detailed spectroscopic analysis, and they were all isolated from the pericarps of A. trifoliata for the first time. Compounds 36 showed in vitro bacteriostatic activity against four assayed Gram-positive bacterial strains. In particular 3 showed antibacterial activity toward MRSA with a MIC value 25 μg/mL, which was more potent than kanamycin (MIC 125 μg/mL). No compounds showed antibacterial activity toward the three Gram-negative bacteria tested. Compounds 4 and 5 showed interesting in vitro growth inhibitory activity against human tumor A549 and HeLa cell lines, with IC50 values ranging from 8.8 and 5.6 μM, respectively. Compounds 1, 2, 5 and 6 were further revealed to show significant in vitro α-glucosidase inhibitory activity with IC50 values from 0.035 to 0.367 mM, which were more potent than the reference compound acarbose (IC50 0.409 mM). Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Synthesis of Extended Uridine Phosphonates Derived from an Allosteric P2Y2 Receptor Ligand
Molecules 2014, 19(4), 4313-4325; doi:10.3390/molecules19044313
Received: 24 February 2014 / Revised: 28 March 2014 / Accepted: 31 March 2014 / Published: 4 April 2014
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Abstract
In this study we report the synthesis of C5/C6-fused uridine phosphonates that are structurally related to earlier reported allosteric P2Y2 receptor ligands. A silyl-Hilbert-Johnson reaction of six quinazoline-2,4-(1H,3H)-dione-like base moieties with a suitable ribofuranosephosphonate afforded the desired [...] Read more.
In this study we report the synthesis of C5/C6-fused uridine phosphonates that are structurally related to earlier reported allosteric P2Y2 receptor ligands. A silyl-Hilbert-Johnson reaction of six quinazoline-2,4-(1H,3H)-dione-like base moieties with a suitable ribofuranosephosphonate afforded the desired analogues after full deprotection. In contrast to the parent 5-(4-fluoropheny)uridine phosphonate, the present extended-base uridine phosphonates essentially failed to modulate the P2Y2 receptor. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Germacranes and m-Menthane from Illicium lanceolatum
Molecules 2014, 19(4), 4326-4337; doi:10.3390/molecules19044326
Received: 15 March 2014 / Revised: 27 March 2014 / Accepted: 28 March 2014 / Published: 4 April 2014
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Abstract
Three new germacrane sesquiterpenes and a new m-menthane monoterpene were isolated together with four known compounds from the pericarp of Illicium lanceolatum, an adulterant to star anise (Illicium verum). All compounds were isolated from Illicium plants for the [...] Read more.
Three new germacrane sesquiterpenes and a new m-menthane monoterpene were isolated together with four known compounds from the pericarp of Illicium lanceolatum, an adulterant to star anise (Illicium verum). All compounds were isolated from Illicium plants for the first time. The absolute stereochemistry of all germacranes and m-menthane was established by a combination of NMR and the modified Mosher’s ester method. The biological activity was evaluated on SH-SY5Y neuroblastoma cell line. (1S,5R,7R)-1,5-Dihydroxygermacra-4(15),10(14),11(12)-triene (at 62.5 µM) and (1R,5R,7R)-1,5-dihydroxygermacra-4(15),10(14),11(12)-triene (at 15.6 µM) promoted the proliferation of SH-SY5Y by 36.2% and 45.8%, respectively, after 48 h incubation, indicating potential neurotrophic activity. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Trithiocyanurate Complexes of Iron, Manganese and Nickel and Their Anticholinesterase Activity
Molecules 2014, 19(4), 4338-4354; doi:10.3390/molecules19044338
Received: 19 December 2013 / Revised: 31 March 2014 / Accepted: 1 April 2014 / Published: 8 April 2014
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Abstract
The complexes of Fe(II), Mn(II) and Ni(II) with a combination of a Schiff base, nitrogen-donor ligand or macrocyclic ligand and trithiocyanuric acid (ttcH3) were prepared and characterized by elemental analysis and spectroscopies. Crystal and molecular structures of the iron complex [...] Read more.
The complexes of Fe(II), Mn(II) and Ni(II) with a combination of a Schiff base, nitrogen-donor ligand or macrocyclic ligand and trithiocyanuric acid (ttcH3) were prepared and characterized by elemental analysis and spectroscopies. Crystal and molecular structures of the iron complex of composition [Fe(L1)](ttcH2)(ClO4)·EtOH·H2O (1), where L1 is Schiff base derived from tris(2-aminoethyl)amine and 2-pyridinecarboxaldehyde, were solved. It was found that the Schiff base is coordinated to the central iron atom by six nitrogens forming deformed octahedral arrangement, whereas trithiocyanurate(1-) anion, perchlorate and solvent molecules are not coordinated. The X-ray structure of the Schiff base sodium salt is also presented and compared with the iron complex. The anticholinesterase activity of the complexes was also studied. Full article
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Open AccessArticle A Novel DNA Nanosensor Based on CdSe/ZnS Quantum Dots and Synthesized Fe3O4 Magnetic Nanoparticles
Molecules 2014, 19(4), 4355-4368; doi:10.3390/molecules19044355
Received: 26 January 2014 / Revised: 1 April 2014 / Accepted: 3 April 2014 / Published: 9 April 2014
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Abstract
Although nanoparticle-enhanced biosensors have been extensively researched, few studies have systematically characterized the roles of nanoparticles in enhancing biosensor functionality. This paper describes a successful new method in which DNA binds directly to iron oxide nanoparticles for use in an optical biosensor. [...] Read more.
Although nanoparticle-enhanced biosensors have been extensively researched, few studies have systematically characterized the roles of nanoparticles in enhancing biosensor functionality. This paper describes a successful new method in which DNA binds directly to iron oxide nanoparticles for use in an optical biosensor. A wide variety of nanoparticles with different properties have found broad application in biosensors because their small physical size presents unique chemical, physical, and electronic properties that are different from those of bulk materials. Of all nanoparticles, magnetic nanoparticles are proving to be a versatile tool, an excellent case in point being in DNA bioassays, where magnetic nanoparticles are often used for optimization of the hybridization and separation of target DNA. A critical step in the successful construction of a DNA biosensor is the efficient attachment of biomolecules to the surface of magnetic nanoparticles. To date, most methods of synthesizing these nanoparticles have led to the formation of hydrophobic particles that require additional surface modifications. As a result, the surface to volume ratio decreases and nonspecific bindings may occur so that the sensitivity and efficiency of the device deteriorates. A new method of large-scale synthesis of iron oxide (Fe3O4) nanoparticles which results in the magnetite particles being in aqueous phase, was employed in this study. Small modifications were applied to design an optical DNA nanosensor based on sandwich hybridization. Characterization of the synthesized particles was carried out using a variety of techniques and CdSe/ZnS core-shell quantum dots were used as the reporter markers in a spectrofluorophotometer. We showed conclusively that DNA binds to the surface of ironoxide nanoparticles without further surface modifications and that these magnetic nanoparticles can be efficiently utilized as biomolecule carriers in biosensing devices. Full article
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Open AccessArticle Rapid Identification of Antioxidant Compounds of Genista saharae Coss. & Dur. by Combination of DPPH Scavenging Assay and HPTLC-MS
Molecules 2014, 19(4), 4369-4379; doi:10.3390/molecules19044369
Received: 12 March 2014 / Revised: 29 March 2014 / Accepted: 1 April 2014 / Published: 9 April 2014
Cited by 6 | PDF Full-text (1637 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Genista species are sources of antioxidant phenolic compounds such as O- and C-glycosylflavonoids and isoflavonoids. A combination of a DPPH scavenging assay with HPTLC-MS, a fast and efficient method for identification of bioactive compounds, has been applied for evaluation of [...] Read more.
Genista species are sources of antioxidant phenolic compounds such as O- and C-glycosylflavonoids and isoflavonoids. A combination of a DPPH scavenging assay with HPTLC-MS, a fast and efficient method for identification of bioactive compounds, has been applied for evaluation of the radical scavenging activity of metabolites from Genista saharae Coss. & Dur. Different organs collected at various periods have been compared. Identification of antioxidant compounds was obtained by elution of the major DPPH-inhibition zones. The resulting HPTLC-MS analysis under moderately polar conditions, coupled to the DPPH results led to the putative identification of two antioxidant isoflavone aglycones: 3',4',5,7-tetrahydroxyisoflavone (1) and ficuisoflavone (3), whereas polar migration conditions led to the identification of the glycosides 5-methoxy-4',7-trihydroxy-8-glucopyranosylisoflavone (4) and 4',5-dihydroxy-7-methoxyisoflavone-4'-O-β-D-gluco-pyranoside (5). Evaluation of percentage of inhibition of DPPH radical by the purified isoflavone 4 from the root extract showed that it affords a moderate contribution to the total radical scavenging activity of the extract. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Synthesis and Biological Evaluation of Novel 2-Methoxypyridylamino-Substituted Riminophenazine Derivatives as Antituberculosis Agents
Molecules 2014, 19(4), 4380-4394; doi:10.3390/molecules19044380
Received: 26 February 2014 / Revised: 31 March 2014 / Accepted: 2 April 2014 / Published: 9 April 2014
Cited by 3 | PDF Full-text (276 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Clofazimine, a member of the riminophenazine class, is one of the few antibiotics that are still active against multidrug-resistant Mycobacterium tuberculosis (M. tuberculosis). However, the clinical utility of this agent is limited by its undesirable physicochemical properties and skin pigmentation [...] Read more.
Clofazimine, a member of the riminophenazine class, is one of the few antibiotics that are still active against multidrug-resistant Mycobacterium tuberculosis (M. tuberculosis). However, the clinical utility of this agent is limited by its undesirable physicochemical properties and skin pigmentation potential. With the goal of maintaining potent antituberculosis activity while improving physicochemical properties and lowering skin pigmentation potential, a series of novel riminophenazine derivatives containing a 2-methoxypyridylamino substituent at the C-2 position of the phenazine nucleus were designed and synthesized. These compounds were evaluated for antituberculosis activity against M. tuberculosis H37Rv and screened for cytotoxicity. Riminophenazines bearing a 3-halogen- or 3,4-dihalogen-substituted phenyl group at the N-5 position exhibited potent antituberculosis activity, with MICs ranging from 0.25~0.01 μg/mL. The 3,4-dihalogen- substituted compounds displayed low cytotoxicity, with IC50 values greater than 64 μg/mL. Among these riminophenazines, compound 15 exhibited equivalent in vivo efficacy against M. tuberculosis infection and reduced skin discoloration potential in an experimental mouse infection model as compared to clofazimine. Compound 15, as compared to clofazimine, also demonstrated improved physicochemical properties and pharmacokinetic profiles with a short half-life and less drug tissue accumulation. This compound is being evaluated as a potential drug candidate for the treatment of multidrug resistant tuberculosis. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Pharmacological Evaluation of Total Alkaloids from Nux Vomica: Effect of Reducing Strychnine Contents
Molecules 2014, 19(4), 4395-4408; doi:10.3390/molecules19044395
Received: 19 July 2013 / Revised: 31 March 2014 / Accepted: 2 April 2014 / Published: 10 April 2014
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Abstract
The aim of the study was to investigate the possibility of improving the therapeutic efficacy of the total alkaloid fraction (TAF) extracted from processed nux vomica by reducing the strychnine contents. Most strychnine was removed from TAF to obtain the modified total [...] Read more.
The aim of the study was to investigate the possibility of improving the therapeutic efficacy of the total alkaloid fraction (TAF) extracted from processed nux vomica by reducing the strychnine contents. Most strychnine was removed from TAF to obtain the modified total alkaloid fraction (MTAF). The toxicity and pharmacokinetics of TAF and MTAF were further investigated and compared besides their antitumor, analgesic and anti-inflammatory activities. The results showed that the ratios of brucine to strychnine were 1:2.05 and 2.2:1 for TAF and MTAF, respectively, and the toxicity of TAF was about 3.17-fold higher than that of MTAF. Compared to brucine alone, the elimination of brucine was found to be inhibited by other alkaloids in TAF or MTAF except strychnine. Significantly increased pharmacological activities when administered by the oral route were obtained with MTAF in comparison to TAF and nux vomica powder (NVP). In summary, MTAF might replace NVP and TAF in the clinical application of Chinese medicine to obtain much higher efficacy. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle HPLC-DPPH Screening Method for Evaluation of Antioxidant Compounds Extracted from Semen Oroxyli
Molecules 2014, 19(4), 4409-4417; doi:10.3390/molecules19044409
Received: 5 March 2014 / Revised: 2 April 2014 / Accepted: 3 April 2014 / Published: 10 April 2014
Cited by 7 | PDF Full-text (1063 KB) | HTML Full-text | XML Full-text | Correction
Abstract
Semen Oroxyli, derived from the seed of Oroxylum indicum L., is a commonly used Traditional Chinese Medicine with beneficial effects against several respiratory disorders. Antioxidative flavonoids may be partly responsible for its medicinal functions. The aim of this study was to rapidly [...] Read more.
Semen Oroxyli, derived from the seed of Oroxylum indicum L., is a commonly used Traditional Chinese Medicine with beneficial effects against several respiratory disorders. Antioxidative flavonoids may be partly responsible for its medicinal functions. The aim of this study was to rapidly determine the antioxidants in Semen Oroxyli based on a HPLC-DPPH method. Four major flavonoids, baicalein-7-O-gentiobioside, baicalein-7-O-glucoside, baicalein, and baicalin, were identified as the active components against DPPH free radicals, which is in accord with the results of our former traditional activity-guided phytochemical study. The oxidative products of the four antioxidant flavonoids were studied in the DPPH spiking HPLC assay, it was suggested that the three active flavonoid glycosides were converted into 5,6-dihydroxy-7-methoxyflavone, which implied that an additional hydroxyl at C-6 in 5,7-dihydroxyflavones plays an important role in the DPPH assay. Full article
Open AccessArticle Synthesis of Regiospecifically Fluorinated Conjugated Dienamides
Molecules 2014, 19(4), 4418-4432; doi:10.3390/molecules19044418
Received: 16 February 2014 / Revised: 22 March 2014 / Accepted: 31 March 2014 / Published: 10 April 2014
Cited by 4 | PDF Full-text (398 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Modular synthesis of regiospecifically fluorinated 2,4-diene Weinreb amides, with defined stereochemistry at both double bonds, was achieved via two sequential Julia-Kocienski olefinations. In the first step, a Z-a-fluorovinyl Weinreb amide unit with a benzothiazolylsulfanyl substituent at the allylic position was assembled. [...] Read more.
Modular synthesis of regiospecifically fluorinated 2,4-diene Weinreb amides, with defined stereochemistry at both double bonds, was achieved via two sequential Julia-Kocienski olefinations. In the first step, a Z-a-fluorovinyl Weinreb amide unit with a benzothiazolylsulfanyl substituent at the allylic position was assembled. This was achieved via condensation of two primary building blocks, namely 2-(benzo[d]thiazol-2-ylsulfonyl)-2-fluoro-N-methoxy-N-methylacetamide (a Julia-Kocienski olefination reagent) and 2-(benzo[d]thiazol-2-ylthio)acetaldehyde (a bifunctional building block). This condensation was highly Z-selective and proceeded in a good 76% yield. Oxidation of benzothiazolylsulfanyl moiety furnished a second-generation Julia-Kocienski olefination reagent, which was used for the introduction of the second olefinic linkage via DBU-mediated condensations with aldehydes, to give (2Z,4E/Z)-dienamides in 50%–74% yield. Although olefinations were 4Z-selective, (2Z,4E/Z)-2-fluoro-2,4-dienamides could be readily isomerized to the corresponding 5-substituted (2Z,4E)-2-fluoro-N-methoxy-N-methylpenta-2,4-dienamides in the presence of catalytic iodine. Full article
(This article belongs to the Special Issue Fluorine Chemistry 2016)
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Open AccessArticle The Effect of Chitin Size, Shape, Source and Purification Method on Immune Recognition
Molecules 2014, 19(4), 4433-4451; doi:10.3390/molecules19044433
Received: 3 March 2014 / Revised: 24 March 2014 / Accepted: 4 April 2014 / Published: 10 April 2014
Cited by 8 | PDF Full-text (1047 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The animal immune response to chitin is not well understood and needs to be investigated further. However, this is a challenging topic to study because of the technical difficulties in purifying chitin, and because this material usually comes associated with contaminating components [...] Read more.
The animal immune response to chitin is not well understood and needs to be investigated further. However, this is a challenging topic to study because of the technical difficulties in purifying chitin, and because this material usually comes associated with contaminating components that can activate the immune system. In this study, improvements to previously described purification protocols were investigated for chitin obtained from different sources, including commercial shellfish, Candida albicans yeast and hyphal cell walls, as well as cell walls of the filamentous fungi Aspergillus fumigatus and Mucor circinelloides. The immune response to these different chitin preparations was tested using human peripheral blood mononuclear cells. In agreement with previous literature, small chitin particles of an average size of 0.2 µm were not immunogenic. On the other hand, bigger chitin particles induced in some cases a pro-inflammatory response. The results of this work suggest that not only the purity and size of the chitin particles, but also their shape can influence immune recognition. Full article
(This article belongs to the Special Issue Chitins and Chitosans)
Open AccessArticle Multielemental Composition of Suet Oil Based on Quantification by Ultrawave/ICP-MS Coupled with Chemometric Analysis
Molecules 2014, 19(4), 4452-4465; doi:10.3390/molecules19044452
Received: 11 March 2014 / Revised: 31 March 2014 / Accepted: 1 April 2014 / Published: 10 April 2014
Cited by 3 | PDF Full-text (2355 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Suet oil (SO) has been used commonly for food and medicine preparation. The determination of its elemental composition has became an important challenge for human safety and health owing to its possible contents of heavy metals or other elements. In this study, [...] Read more.
Suet oil (SO) has been used commonly for food and medicine preparation. The determination of its elemental composition has became an important challenge for human safety and health owing to its possible contents of heavy metals or other elements. In this study, ultrawave single reaction chamber microwave digestion (Ultrawave) and inductively coupled plasma-mass spectrometry (ICP-MS) analysis was performed to determine 14 elements (Pb, As, Hg, Cd, Fe, Cu, Mn, Ti, Ni, V, Sr, Na, Ka and Ca) in SO samples. Furthermore, the multielemental content of 18 SO samples, which represented three different sources in China: Qinghai, Anhui and Jiangsu, were evaluated and compared. The optimal ultrawave digestion conditions, namely, the optimal time (35 min), temperature (210 °C) and pressure (90 bar), were screened by Box-Behnken design (BBD). Eighteen samples were successfully classified into three groups by principal component analysis (PCA) according to the contents of 14 elements. The results showed that all SO samples were rich in elements, but with significant differences corresponding to different origins. The outliers and majority of SO could be discriminated by PCA according to the multielemental content profile. The results highlighted that the element distribution was associated with the origins of SO samples. The proposed ultrawave digestion system was quite efficient and convenient, which could be mainly attributed to its high pressure and special high-throughput for the sample digestion procedure. Our established method could be useful for the quality control and standardization of elements in SO samples and products. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Quantitative Analysis of the Flavonoid Glycosides and Terpene Trilactones in the Extract of Ginkgo biloba and Evaluation of Their Inhibitory Activity towards Fibril Formation of β-Amyloid Peptide
Molecules 2014, 19(4), 4466-4478; doi:10.3390/molecules19044466
Received: 13 March 2014 / Revised: 1 April 2014 / Accepted: 3 April 2014 / Published: 10 April 2014
Cited by 9 | PDF Full-text (367 KB) | HTML Full-text | XML Full-text
Abstract
The standard extract of Ginkgo biloba leaves (EGb761) is used clinically in Europe for the symptomatic treatment of impaired cerebral function in primary degenerative dementia syndromes, and the results of numerous in vivo and in vitro studies have supported such clinical use. [...] Read more.
The standard extract of Ginkgo biloba leaves (EGb761) is used clinically in Europe for the symptomatic treatment of impaired cerebral function in primary degenerative dementia syndromes, and the results of numerous in vivo and in vitro studies have supported such clinical use. The abnormal production and aggregation of amyloid β peptide (Aβ) and the deposition of fibrils in the brain are regarded as key steps in the onset of Alzheimer’s Disease (AD), and the inhibition of Aβ aggregation and destabilization of the preformed fibrils represent viable approaches for the prevention and treatment of AD. Flavonoid glycosides and terpene trilactones (TTLs) are the two main components of EGb761 which represent 24 and 6% of the overall content, respectively. In our research, seven abundant flavonoid glycosides 17 were isolated from the extract of Ginkgo biloba leaves and characterized by spectroscopic analysis. Furthermore, an ultra-high performance liquid chromatography method was established for the simultaneous quantification of these seven flavonoids. The inhibitory activities of these flavonoids, as well as four TTLs, i.e., ginkgolides A, B, and C and bilobalide (compounds 811), were evaluated towards Aβ42 fibril formation using a thioflavin T fluorescence assay. It was found that three flavonoids 1, 3 and 4 exhibited moderate inhibitory activities, whereas the other four flavonoids 2, 5, 6 and 7, as well as the four terpene trilactones, showed poor activity. This is the first report of the inhibition of Aβ fibril formation of two characteristic acylated flavonoid glycosides 6, 7 in Ginkgo leaves, on the basis of which the structure-activity relationship of these flavonoids 17 was discussed. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Studies on the Bioactive Flavonoids Isolated from Pithecellobium clypearia Benth
Molecules 2014, 19(4), 4479-4490; doi:10.3390/molecules19044479
Received: 28 January 2014 / Revised: 30 March 2014 / Accepted: 3 April 2014 / Published: 10 April 2014
Cited by 3 | PDF Full-text (434 KB) | HTML Full-text | XML Full-text
Abstract
One new flavonoid named (2R,3R)-7-O-galloylplumbocatechin A (1) and three known flavonoids, (−)-5,3',4',5'-tetrahydroxyflavan-7-gallate (2), (+)-3,5,3',4',5'-penta-hydroxyflavan-7-gallate (3), and (−)-7,4'-di-O-galloyltricetiflavan (4), were isolated from Pithecellobium clypearia Benth. Their structures [...] Read more.
One new flavonoid named (2R,3R)-7-O-galloylplumbocatechin A (1) and three known flavonoids, (−)-5,3',4',5'-tetrahydroxyflavan-7-gallate (2), (+)-3,5,3',4',5'-penta-hydroxyflavan-7-gallate (3), and (−)-7,4'-di-O-galloyltricetiflavan (4), were isolated from Pithecellobium clypearia Benth. Their structures were elucidated based on spectroscopic analysis, including homonuclear and heteronuclear correlation NMR (HSQC and HMBC) experiments. In vitro assays, compounds 1 and 2 showed moderate inhibitory effects against influenza H1N1 virus neuraminidase (NA). Compounds 14 were all found to inhibit the expression of proinflammatory cytokines IL-6 or MCP-1 induced by influenza H1N1 virus in human A549 lung carcinoma cells. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Inhibition and Biochemical Characterization of Methicillin-Resistant Staphylococcus aureus Shikimate Dehydrogenase: An in Silico and Kinetic Study
Molecules 2014, 19(4), 4491-4509; doi:10.3390/molecules19044491
Received: 6 February 2014 / Revised: 3 April 2014 / Accepted: 4 April 2014 / Published: 10 April 2014
Cited by 1 | PDF Full-text (2040 KB) | HTML Full-text | XML Full-text
Abstract
Methicillin-resistant Staphylococcus auerus (MRSA) strains are having a major impact worldwide, and due to their resistance to all β-lactams, an urgent need for new drugs is emerging. In this regard, the shikimate pathway is considered to be one of the metabolic features [...] Read more.
Methicillin-resistant Staphylococcus auerus (MRSA) strains are having a major impact worldwide, and due to their resistance to all β-lactams, an urgent need for new drugs is emerging. In this regard, the shikimate pathway is considered to be one of the metabolic features of bacteria and is absent in humans. Therefore enzymes involved in this route, such as shikimate dehydrogenase (SDH), are considered excellent targets for discovery of novel antibacterial drugs. In this study, the SDH from MRSA (SaSDH) was characterized. The results showed that the enzyme is a monomer with a molecular weight of 29 kDa, an optimum temperature of 65 °C, and a maximal pH range of 9–11 for its activity. Kinetic studies revealed that SDH showed Michaelis-Menten kinetics toward both substrates (shikimate and NADP+). Initial velocity analysis suggested that SaSDH catalysis followed a sequential random mechanism. Additionally, a tridimensional model of SaSDH was obtained by homology modeling and validated. Through virtual screening three inhibitors of SaSDH were found (compounds 238, 766 and 894) and their inhibition constants and mechanism were obtained. Flexible docking studies revealed that these molecules make interactions with catalytic residues. The data of this study could serve as starting point in the search of new chemotherapeutic agents against MRSA. Full article
(This article belongs to the Special Issue In-Silico Drug Design and In-Silico Screening)
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Open AccessArticle Different Accumulation Profiles of Multiple Components Between Pericarp and Seed of Alpinia oxyphylla Capsular Fruit as Determined by UFLC-MS/MS
Molecules 2014, 19(4), 4510-4523; doi:10.3390/molecules19044510
Received: 14 January 2014 / Revised: 30 March 2014 / Accepted: 1 April 2014 / Published: 10 April 2014
Cited by 7 | PDF Full-text (424 KB) | HTML Full-text | XML Full-text
Abstract
Plant secondary metabolites are known to not only play a key role in the adaptation of plants to their environment, but also represent an important source of active pharmaceuticals. Alpinia oxyphylla capsular fruits, made up of seeds and pericarps, are commonly used [...] Read more.
Plant secondary metabolites are known to not only play a key role in the adaptation of plants to their environment, but also represent an important source of active pharmaceuticals. Alpinia oxyphylla capsular fruits, made up of seeds and pericarps, are commonly used in traditional East Asian medicines. In clinical utilization of these capsular fruits, inconsistent processing approaches (i.e., hulling pericarps or not) are employed, with the potential of leading to differential pharmacological effects. Therefore, an important question arises whether the content levels of pharmacologically active chemicals between the seeds and pericarps of A. oxyphylla are comparable. Nine secondary metabolites present in A. oxyphylla capsular fruits, including flavonoids (e.g., tectochrysin, izalpinin, chrysin, apigenin-4',7-dimethylether and kaempferide), diarylheptanoids (e.g., yakuchinone A and B and oxyphyllacinol) and sesquiterpenes (e.g., nootkatone), were regarded as representative constituents with putative pharmacological activities. This work aimed to investigate the abundance of the nine constituents in the seeds and pericarps of A. oxyphylla. Thirteen batches of A. oxyphylla capsular fruits were gathered from different production regions. Accordingly, an ultra-fast high performance liquid chromatography/quadrupole tandem mass spectrometry (UFLC-MS/MS) method was developed and validated. We found that: (1) the nine secondary metabolites were differentially concentrated in seeds and fruit capsules; (2) nootkatone is predominantly distributed in the seeds; in contrast, the flavonoids and diarylheptanoids are mainly deposited in the capsules; and (3) the content levels of the nine secondary metabolites occurring in the capsules varied greatly among different production regions, although the nootkatone levels in the seeds were comparable among production regions. These results are helpful to evaluating and elucidating pharmacological activities of A. oxyphylla capsular fruits. Additionally, it may be of interest to elucidate the mechanisms involved in the distinct accumulation profiles of these secondary metabolites between seeds and pericarps. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Comparative Study of Tributyltin Adsorption onto Mesoporous Silica Functionalized with Calix[4]arene, p-tert-Butylcalix[4]arene and p-Sulfonatocalix[4]arene
Molecules 2014, 19(4), 4524-4547; doi:10.3390/molecules19044524
Received: 27 February 2014 / Revised: 3 April 2014 / Accepted: 4 April 2014 / Published: 10 April 2014
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Abstract
The adsorption of tributyltin (TBT), onto three mesoporous silica adsorbents functionalized with calix[4]arene, p-tert-butylcalix[4]arene and p-sulfonatocalix[4]arene (MCM-TDI-C4, MCM-TDI-PC4 and MCM-TDI-C4S, respectively) has been compared. Batch adsorption experiments were carried out and the effect of contact time, initial TBT concentration, pH [...] Read more.
The adsorption of tributyltin (TBT), onto three mesoporous silica adsorbents functionalized with calix[4]arene, p-tert-butylcalix[4]arene and p-sulfonatocalix[4]arene (MCM-TDI-C4, MCM-TDI-PC4 and MCM-TDI-C4S, respectively) has been compared. Batch adsorption experiments were carried out and the effect of contact time, initial TBT concentration, pH and temperature were studied. The Koble–Corrigan isotherm was the most suitable for data fitting. Based on a Langmuir isotherm model, the maximum adsorption capacities were 12.1212, 16.4204 and 7.5757 mg/g for MCM-TDI-C4, MCM-TDI-PC4 and MCM-TDI-C4S, respectively. The larger uptake and stronger affinity of MCM-TDI-PC4 than MCM-TDI-C4 and MCM-TDI-C4S probably results from van der Waals interactions and the pore size distribution of MCM-TDI-PC4. Gibbs free energies for the three adsorption processes of TBT presented a negative value, reflecting that TBT/surface interactions are thermodynamic favorable and spontaneous. The interaction processes were accompanied by an increase of entropy value for MCM-TDI-C4 and MCM-TDI-C4S (43.7192 and 120.7609 J/mol K, respectively) and a decrease for MCM-TDI-PC4 (−37.4704 J/mol K). It is obviously observed that MCM-TDI-PC4 spontaneously adsorbs TBT driven mainly by enthalpy change, while MCM-TDI-C4 and MCM-TDI-C4S do so driven mainly by entropy changes. Full article
Open AccessArticle Five Withanolides from the Leaves of Datura metel L. and Their Inhibitory Effects on Nitric Oxide Production
Molecules 2014, 19(4), 4548-4559; doi:10.3390/molecules19044548
Received: 7 March 2014 / Revised: 4 April 2014 / Accepted: 8 April 2014 / Published: 11 April 2014
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Abstract
Four new withanolides named dmetelins A–D (compounds 14), along with the known compound 7α,27-dihydroxy-1-oxo-witha-2,5,24-trienolide (5) were isolated from the leaves of Datura metel L. (Solanaceae). Their structures were elucidated on the basis of detailed analysis [...] Read more.
Four new withanolides named dmetelins A–D (compounds 14), along with the known compound 7α,27-dihydroxy-1-oxo-witha-2,5,24-trienolide (5) were isolated from the leaves of Datura metel L. (Solanaceae). Their structures were elucidated on the basis of detailed analysis of 1D and 2D NMR and mass spectrometry data. All the compounds were evaluated for their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells. Compounds 1, 4 and 5 showed significant inhibitory activities, and compounds 2 and 3 showed moderate inhibitory activities with IC50 values of 17.8, 11.6, 14.9, 33.3 and 28.6 μM, respectively. Full article
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Open AccessArticle Seasonal Variation of the Chemical Composition and Antimicrobial and Cytotoxic Activities of the Essential Oils from Inga laurina (Sw.) Willd.
Molecules 2014, 19(4), 4560-4577; doi:10.3390/molecules19044560
Received: 31 January 2014 / Revised: 26 March 2014 / Accepted: 2 April 2014 / Published: 11 April 2014
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Abstract
The seasonal chemical composition of essential oils from Inga laurina was determined by GC/MS. In the stem bark’s essential oil extracted during the dry season, the presence of terpenoids (30.05%) stood out, and phytol (9.76%) was the major compound identified. For the [...] Read more.
The seasonal chemical composition of essential oils from Inga laurina was determined by GC/MS. In the stem bark’s essential oil extracted during the dry season, the presence of terpenoids (30.05%) stood out, and phytol (9.76%) was the major compound identified. For the stem bark oil obtained during the rainy season, in addition to terpenoids (26.63%), a large amount of fatty acids (46.84%) were identified, in particular palmitic acid (25.40%). Regarding the leaves’ essential oil obtained in the dry season, esters (42.35%) were the main components. The main ester present was (Z)-hex-3-enyl benzoate (10.15%) and the major compound of this oil was (Z)-hex-3-en-1-ol (14.23%). Terpenoids (33.84%), long-chain alkanes (27.04%) and fatty acids (21.72%) were the main components of the essential oil from leaves in the rainy season. Phytol (33.21%), nonacosane (21.95%) and palmitic acid (15.20%) were the major compounds identified. The antimicrobial activity against aerobic and anaerobic oral bacteria was evaluated by the microdilution broth method and cytotoxic activity was carried out with Vero cells. The essential oils from the rainy season showed a better inhibition of the bacterial growth with Minimal Inhibitory Concentrations (MIC) values of 25 or 50 µg·mL−1 for aerobic bacteria, and high selectivity against bacteria was observed. The large amount of fatty acids in rainy season oils may be related to the better inhibitory effects observed. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle MALDI-TOF MS Analysis of Cellodextrins and Xylo-oligosaccharides Produced by Hindgut Homogenates of Reticulitermes santonensis
Molecules 2014, 19(4), 4578-4594; doi:10.3390/molecules19044578
Received: 11 February 2014 / Revised: 2 April 2014 / Accepted: 4 April 2014 / Published: 11 April 2014
PDF Full-text (812 KB) | HTML Full-text | XML Full-text
Abstract
Hindgut homogenates of the termite Reticulitermes santonensis were incubated with carboxymethyl cellulose (CMC), crystalline celluloses or xylan substrates. Hydrolysates were analyzed with matrix-assisted laser desorption/ionization coupled to time-of-flight mass spectrometry (MALDI-TOF MS). The method was first set up using acid hydrolysis analysis [...] Read more.
Hindgut homogenates of the termite Reticulitermes santonensis were incubated with carboxymethyl cellulose (CMC), crystalline celluloses or xylan substrates. Hydrolysates were analyzed with matrix-assisted laser desorption/ionization coupled to time-of-flight mass spectrometry (MALDI-TOF MS). The method was first set up using acid hydrolysis analysis to characterize non-enzymatic profiles. Commercial enzymes of Trichoderma reesei or T. longibrachiatum were also tested to validate the enzymatic hydrolysis analysis. For CMC hydrolysis, data processing and visual display were optimized to obtain comprehensive profiles and allow rapid comparison and evaluation of enzymatic selectivity, according to the number of substituents of each hydrolysis product. Oligosaccharides with degrees of polymerization (DPs) ranging from three to 12 were measured from CMC and the enzymatic selectivity was demonstrated. Neutral and acidic xylo-oligosaccharides with DPs ranging from three to 11 were measured from xylan substrate. These results are of interest for lignocellulose biomass valorization and demonstrated the potential of termites and their symbiotic microbiota as a source of interesting enzymes for oligosaccharides production. Full article
(This article belongs to the Special Issue Oligosaccharides and Glyco-Conjugates)
Open AccessArticle In Vitro Antioxidant and Cytotoxic Activity of Some Synthetic Riparin-Derived Compounds
Molecules 2014, 19(4), 4595-4607; doi:10.3390/molecules19044595
Received: 16 October 2013 / Revised: 17 January 2014 / Accepted: 23 January 2014 / Published: 11 April 2014
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Abstract
This study aimed to study the in vitro antioxidant activity and cytotoxicity on tumor cells lines of six synthetic substances derived from riparins. All the substances showed antioxidant activity and riparins C, D, E, F presented cell growth inhibition rates greater than [...] Read more.
This study aimed to study the in vitro antioxidant activity and cytotoxicity on tumor cells lines of six synthetic substances derived from riparins. All the substances showed antioxidant activity and riparins C, D, E, F presented cell growth inhibition rates greater than 70%, suggesting that these molecules have antitumor properties. These substances also caused greater than 80% releases of cytoplasmic lactate dehydrogenase enzyme (LDH). Although the antioxidant and antitumor properties presented herein require further assessment, the outcomes indicate that these novel riparins are promising biologically active compounds. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Anti-Inflammatory Triterpenoids from the Stems of Microtropis Fokienensis
Molecules 2014, 19(4), 4608-4623; doi:10.3390/molecules19044608
Received: 3 March 2014 / Revised: 9 April 2014 / Accepted: 9 April 2014 / Published: 14 April 2014
Cited by 2 | PDF Full-text (445 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Three new ursane- and four new oleanane- type triterpenoids 17 were isolated, along with six known compounds 813, from the methanolic extract of Microtropis fokienensis. All structures were elucidated by mass and NMR spectroscopic methods. The [...] Read more.
Three new ursane- and four new oleanane- type triterpenoids 17 were isolated, along with six known compounds 813, from the methanolic extract of Microtropis fokienensis. All structures were elucidated by mass and NMR spectroscopic methods. The isolates 410 and known compounds 1417 that were previously isolated from this material were evaluated for anti-inflammatory activity based on effects against superoxide anion generation and elastase release by neutrophils in response to fMLP/CB. 11α,30-Dihydroxy-2,3-seco-olean-12-en-2,3-dioic anhydride (7) was the first triterpene anhydride from the genus of Microtropis to have the ring A expanded to a seven-membered ring; it showed significant anti-inflammatory activity against superoxide anion generation and elastase release. Unexpectedly, 30-hydroxy-2,3-seco-lup-20(29)-ene-2,3-dioic acid (17) showed the best effect against superoxide anion generation and elastase release with IC50 values of 0.06 ± 0.01 and 1.03 ± 0.35 µg/mL, respectively. Compound 17 had a dioic acid function, and compound 7 had an anhydride function modification in ring A; both showed promising activity in the target assays. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Green Synthesis of Silver Nanoparticles using Achillea biebersteinii Flower Extract and Its Anti-Angiogenic Properties in the Rat Aortic Ring Model
Molecules 2014, 19(4), 4624-4634; doi:10.3390/molecules19044624
Received: 16 February 2014 / Revised: 30 March 2014 / Accepted: 4 April 2014 / Published: 15 April 2014
Cited by 14 | PDF Full-text (506 KB) | HTML Full-text | XML Full-text
Abstract
Silver nanoparticles display unique physical and biological properties which have attracted intensive research interest because of their important medical applications. In this study silver nanoparticles (Ab.Ag-NPs) were synthesized for biomedical applications using a completely green biosynthetic method using Achillea biebersteinii [...] Read more.
Silver nanoparticles display unique physical and biological properties which have attracted intensive research interest because of their important medical applications. In this study silver nanoparticles (Ab.Ag-NPs) were synthesized for biomedical applications using a completely green biosynthetic method using Achillea biebersteinii flowers extract. The structure and properties of Ab.Ag-NPs were investigated using UV-visible spectroscopic techniques, transmission electron microscopy (TEM), zeta potential and energy dispersive X-ray spectrometers (EDS). The UV-visible spectroscopic analysis showed the absorbance peak at 460 nm, which indicates the synthesis of silver nanoparticles. The average particle diameter as determined by TEM was found to be 12 ± 2 nm. The zeta potential analysis indicated that Ab.Ag-NPs have good stability EDX analysis also exhibits presentation of silver element. As angiogenesis is an important phenomenon and as growth factors imbalance in this process causes the acceleration of several diseases including cancer, the anti-angiogenic properties of Ab.Ag-NPs were evaluated using the rat aortic ring model. The results showed that Ab.Ag-NPs (200 μg/mL) lead to a 50% reduction in the length and number of vessel-like structures. The synthesized silver nanoparticles from the Achillea biebersteinii flowers extract, which do not involve any harmful chemicals were well-dispersed and stabilized through this green method and showed potential therapeutic benefits against angiogenesis. Full article
Open AccessArticle Silymarin Induces Expression of Pancreatic Nkx6.1 Transcription Factor and β-Cells Neogenesis in a Pancreatectomy Model
Molecules 2014, 19(4), 4654-4668; doi:10.3390/molecules19044654
Received: 19 December 2013 / Revised: 21 March 2014 / Accepted: 31 March 2014 / Published: 15 April 2014
Cited by 6 | PDF Full-text (4711 KB) | HTML Full-text | XML Full-text
Abstract
A physio-pathological feature of diabetes mellitus is a significant reduction of β-pancreatic cells. The growth, differentiation and function maintenance of these cells is directed by transcription factors. Nkx6.1 is a key transcription factor for the differentiation, neogenesis and maintenance of β-pancreatic cells. [...] Read more.
A physio-pathological feature of diabetes mellitus is a significant reduction of β-pancreatic cells. The growth, differentiation and function maintenance of these cells is directed by transcription factors. Nkx6.1 is a key transcription factor for the differentiation, neogenesis and maintenance of β-pancreatic cells. We reported that silymarin restores normal morphology and endocrine function of damaged pancreatic tissue after alloxan-induced diabetes mellitus in rats. The aim of this study was to analyze the effect of silymarin on Nkx6.1 transcription factor expression and its consequence in β cells neogenesis. Sixty male Wistar rats were partially pancreatectomized and divided into twelve groups. Six groups were treated with silymarin (200 mg/Kg p.o) for periods of 3, 7, 14, 21, 42 and 63 days. Additionally, an unpancreatectomized control group was used. Nkx6.1 and insulin gene expression were assessed by RT-PCR assay in total pancreatic RNA. β-Cell neogenesis was determined by immunoperoxidase assay. Silymarin treated group showed an increase of Nkx6.1 and insulin genic expression. In this group, there was an increment of β-cell neogenesis in comparison to pancreatectomized untreated group. Silymarin treatment produced a rise in serum insulin and serum glucose normalization. These results suggest that silymarin may improve the reduction of β pancreatic cells observed in diabetes mellitus. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Cornu Cervi Pantotrichum Supplementation Improves Exercise Performance and Protects against Physical Fatigue in Mice
Molecules 2014, 19(4), 4669-4680; doi:10.3390/molecules19044669
Received: 24 February 2014 / Revised: 11 April 2014 / Accepted: 11 April 2014 / Published: 15 April 2014
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Abstract
Cornu cervi pantotrichum (CCP) is a well-known yang-invigorating agent used in traditional Chinese medicine that can nourish the blood, tonify qi, and invigorate bones and tendons with multifunctional bioactivities. However, evidence on the effects of CCP on exercise performance and physical fatigue [...] Read more.
Cornu cervi pantotrichum (CCP) is a well-known yang-invigorating agent used in traditional Chinese medicine that can nourish the blood, tonify qi, and invigorate bones and tendons with multifunctional bioactivities. However, evidence on the effects of CCP on exercise performance and physical fatigue is limited. We evaluated the potential beneficial effects of ethanolic extract from CCP on ergogenic and antifatigue functions following a physiological challenge. Male ICR mice from four groups (n = 8 per group) were orally administered CCP for 14 days at 0, 2054, and 4108 mg/kg/day, and were respectively designated as the vehicle, CCP-1X, and CCP-2X groups. The physical performance and antifatigue function were evaluated using forelimb grip strength and exhaustive swimming time as well as serum levels of lactate, ammonia, glucose, and creatine kinase after a 15-min swimming exercise. The results indicated that CCP-1X supplementation significantly improved grip strength; reduced fatigue-associated biochemical indices, including lactate and ammonia levels; and ameliorated skeletal muscle injury induced by acute exercise challenge. A trend analysis revealed that CCP supplementation significantly increased grip strength and dose-dependently reduced serum alkaline phosphatase, uric acid, triacylglycerol, and glucose levels in healthy mice. Therefore, CCP is a potential agent with an antifatigue pharmacological effect. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle In Vitro Antioxidant Activities, Free Radical Scavenging Capacity, and Tyrosinase Inhibitory of Flavonoid Compounds and Ferulic Acid from Spiranthes sinensis (Pers.) Ames
Molecules 2014, 19(4), 4681-4694; doi:10.3390/molecules19044681
Received: 24 January 2014 / Revised: 2 April 2014 / Accepted: 3 April 2014 / Published: 15 April 2014
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Abstract
In this study, ultrasound-assisted extraction (UAE) and other methods of extracting flavonoid compounds and ferulic acid (FA) from S. sinensis were investigated. Five different extraction methods, including water extraction (W), water extraction using UAE (W+U), 75% ethanol extraction (E), 75% ethanol extraction [...] Read more.
In this study, ultrasound-assisted extraction (UAE) and other methods of extracting flavonoid compounds and ferulic acid (FA) from S. sinensis were investigated. Five different extraction methods, including water extraction (W), water extraction using UAE (W+U), 75% ethanol extraction (E), 75% ethanol extraction using UAE (E+U), and supercritical CO2 extraction (SFE) were applied in the extraction of bioactive compounds (flavonoids and ferulic acid) in order to compare their efficiency. The highest yield of flavonoids (4.28 mg/g) and ferulic acid (4.13 mg/g) content was detected in the E+U extract. Furthermore, S. sinensis extracts obtained by E+U show high antioxidant activity, and IC50 values of 0.47 mg/mL for DPPH radicals and 0.205 mg/mL for metal chelating activity. The total antioxidant assay shows superoxide radical scavenging capacity and in vitro mushroom tyrosinase inhibition in a dose-dependent manner, suggesting that E+U can be used for extraction of bioactive compounds from S. sinensis. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Molecular Disorder in (‒)-Encecanescin
Molecules 2014, 19(4), 4695-4707; doi:10.3390/molecules19044695
Received: 20 January 2014 / Revised: 3 April 2014 / Accepted: 4 April 2014 / Published: 15 April 2014
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Abstract
(‒)-Encecanescin (1) has been isolated from the leaves of Eupatorium aschembornianum. Two conformers are present in the crystal structure as a result of molecular disorder. The structure of 1 was established by 1H- and 13C-NMR spectroscopy in [...] Read more.
(‒)-Encecanescin (1) has been isolated from the leaves of Eupatorium aschembornianum. Two conformers are present in the crystal structure as a result of molecular disorder. The structure of 1 was established by 1H- and 13C-NMR spectroscopy in CDCl3 solution using 2D NMR techniques (gHSQC, gHMBC and NOESY). A Monte Carlo random search using molecular mechanics followed by the geometry optimization of each minimum energy structure using density functional theory (DFT) calculations at the B3LYP/6–31G* level and a Boltzmann analysis of the total energies generated accurate molecular models describing the conformational behavior of 1. The three most stable conformers 24 of compound 1 were reoptimized at the B3LYP/6-311++G(d,p) level of theory using CHCl3 as a solvent. Correlations between the experimental 1H- and 13C-NMR chemical shifts (δexp) have been found, and the GIAO/B3LYP/6-311++G(d,p) calculated magnetic isotropic shielding tensors (σcalc) for conformers 2 and 3, δexp = a + b σcalc, are reported. A good linear relationship between the experimental and calculated NMR data has been obtained for protons and carbon atoms. Full article
(This article belongs to the Section Molecular Diversity)
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Open AccessArticle Pharmacological and Structure-Activity Relationship Evaluation of 4-aryl-1-Diphenylacetyl(thio)semicarbazides
Molecules 2014, 19(4), 4745-4759; doi:10.3390/molecules19044745
Received: 7 February 2014 / Revised: 27 March 2014 / Accepted: 3 April 2014 / Published: 16 April 2014
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Abstract
This article describes the synthesis of six 4-aryl-(thio)semicarbazides (series a and b) linked with diphenylacetyl moiety along with their pharmacological evaluation on the central nervous system in mice and computational studies, including conformational analysis and electrostatic properties. All thiosemicarbazides (series b [...] Read more.
This article describes the synthesis of six 4-aryl-(thio)semicarbazides (series a and b) linked with diphenylacetyl moiety along with their pharmacological evaluation on the central nervous system in mice and computational studies, including conformational analysis and electrostatic properties. All thiosemicarbazides (series b) were found to exhibit strong antinociceptive activity in the behavioural model. Among them, compound 1-diphenylacetyl-4-(4-methylphenyl)thiosemicarbazide 1b was found to be the most potent analgesic agent, whose activity is connected with the opioid system. For compounds from series a significant anti-serotonergic effect, especially for compound 1-diphenylacetyl-4-(4-methoxyphenyl)semicarbazide 2b was observed. The computational studies strongly support the obtained results. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Spectroscopic and Molecular Docking Studies of the in Vitro Interaction between Puerarin and Cytochrome P450
Molecules 2014, 19(4), 4760-4769; doi:10.3390/molecules19044760
Received: 7 February 2014 / Revised: 5 April 2014 / Accepted: 9 April 2014 / Published: 16 April 2014
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Abstract
Puerarin, an isoflavone glycoside extracted from Pueraria plants, has various medical functions. Cytochrome P450s (CYPs) are crucial phase I metabolizing enzymes, which have been spotlighted for their effects on drug metabolism. The interaction between puerarin and CYPs (CYP1A2 and CYP2D6) was investigated [...] Read more.
Puerarin, an isoflavone glycoside extracted from Pueraria plants, has various medical functions. Cytochrome P450s (CYPs) are crucial phase I metabolizing enzymes, which have been spotlighted for their effects on drug metabolism. The interaction between puerarin and CYPs (CYP1A2 and CYP2D6) was investigated by fluorescence, UV-Vis and circular dichroism spectroscopies, as well as molecular docking, to explore the underlying mechanism under simulated physiological conditions. The molecular docking results indicated that puerarin interacted with CYPs mainly by hydrophobic force and hydrogen bonding. The fluorescences of CYPs were quenched statically. Binding constants (Ka) and number of binding sites (n) at different temperatures were calculated, with the results being consistent with those of molecular docking. At the same temperature, puerarin bound to CYP1A2 more weakly than it did to CYP2D6. UV-Vis and circular dichroism spectroscopies confirmed the micro-environmental and conformational changes of CYP1A2 and CYP2D6. The findings provide reliable evidence for clarifying the structures and functions of CYPs. Full article
Open AccessArticle Optimization of Fermentation Conditions for the Production of the M23 Protease Pseudoalterin by Deep-Sea Pseudoalteromonas sp. CF6-2 with Artery Powder as an Inducer
Molecules 2014, 19(4), 4779-4790; doi:10.3390/molecules19044779
Received: 12 March 2014 / Revised: 12 April 2014 / Accepted: 14 April 2014 / Published: 16 April 2014
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Abstract
Proteases in the M23 family have specific activities toward elastin and bacterial peptidoglycan. The peptidoglycan-degrading property makes these proteases have potential as novel antimicrobials. Because M23 proteases cannot be maturely expressed in Escherichia coli, it is significant to improve the production [...] Read more.
Proteases in the M23 family have specific activities toward elastin and bacterial peptidoglycan. The peptidoglycan-degrading property makes these proteases have potential as novel antimicrobials. Because M23 proteases cannot be maturely expressed in Escherichia coli, it is significant to improve the production of these enzymes in their wild strains. Pseudoalterin is a new M23 protease secreted by the deep-sea bacterium Pseudoalteromonas sp. CF6-2. In this study, the fermentation conditions of strain CF6-2 for pseudoalterin production were optimized using single factor experiments and response surface methodology to improve the enzyme yield. To reduce the fermentation cost, bovine artery powder instead of elastin was determined as a cheap and efficient inducer. Based on single factor experiments, artery powder content, culture temperature and culture time were determined as the main factors influencing pseudoalterin production and were further optimized by the central composite design. The optimal values of these factors were determined as: artery powder of 1.2%, culture temperature of 20.17 °C and culture time of 28.04 h. Under the optimized conditions, pseudoalterin production reached 100.02 ± 9.0 U/mL, more than twice of that before optimization. These results lay a good foundation for developing the biotechnological potential of pseudoalterin. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Synthesis and Anti-hypertensive Effects of the Twin Drug of Nicotinic Acid and Quercetin Tetramethyl Ether
Molecules 2014, 19(4), 4791-4801; doi:10.3390/molecules19044791
Received: 10 March 2014 / Revised: 8 April 2014 / Accepted: 9 April 2014 / Published: 16 April 2014
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Abstract
A novel twin drug consisting of nicotinic acid (VB3) and quercetin tetramethyl ether (QTME) has been synthesized as an antihypertensive in a total yield of 79.2% through methylation, hydrolysis, acylation and esterification starting from rutin. The structures of synthesized compounds were elucidated [...] Read more.
A novel twin drug consisting of nicotinic acid (VB3) and quercetin tetramethyl ether (QTME) has been synthesized as an antihypertensive in a total yield of 79.2% through methylation, hydrolysis, acylation and esterification starting from rutin. The structures of synthesized compounds were elucidated by 1H-NMR, 13C-NMR and elemental analysis. The anti-hypertensive effects of an oral daily dose (15 mg/kg) of the synthesized compounds in spontaneously hypertensive (SHR) rats and normotensive Wistar Kyoto (WKY) rats were analysed. The data demonstrate that the twin drug VB3-QTME both reduces the elevated blood pressure and prolongs the action time in SHR rats without effect on WKY rats. However, definitive evidence of a precise mechanism of action by which VB3-QTME might decrease blood pressure remains elusive. Based on the results, the therapeutic potential of this twin drug is discussed. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Three New Triterpene Esters from Pumpkin (Cucurbita maxima) Seeds
Molecules 2014, 19(4), 4802-4813; doi:10.3390/molecules19044802
Received: 7 February 2014 / Revised: 27 March 2014 / Accepted: 8 April 2014 / Published: 16 April 2014
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Abstract
Three new multiflorane-type triterpene esters, i.e. 7α-hydroxymultiflor-8-ene-3α,29-diol 3-acetate-29-benzoate (1), 7α-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (2), and 7β-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (3), were isolated from seeds of Cucurbita maxima, along with the known compound, multiflora-7,9(11)-diene-3α,29-diol 3,29-dibenzoate (4). Compound 1 [...] Read more.
Three new multiflorane-type triterpene esters, i.e. 7α-hydroxymultiflor-8-ene-3α,29-diol 3-acetate-29-benzoate (1), 7α-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (2), and 7β-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (3), were isolated from seeds of Cucurbita maxima, along with the known compound, multiflora-7,9(11)-diene-3α,29-diol 3,29-dibenzoate (4). Compound 1 exhibited melanogenesis inhibitory activities comparable with those of arbutin. In cytotoxicity assays, compounds 1 and 3 exhibited weak cytotoxicity, with IC50 values of 34.5–93.7 μM against HL-60 and P388 cells. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Exploring the Phe-Gly Dipeptide-Derived Piperazinone Scaffold in the Search for Antagonists of the Thrombin Receptor PAR1
Molecules 2014, 19(4), 4814-4846; doi:10.3390/molecules19044814
Received: 4 February 2014 / Revised: 8 April 2014 / Accepted: 13 April 2014 / Published: 16 April 2014
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Abstract
A series of Phe-Gly dipeptide-derived piperazinones containing an aromatic urea moiety and a basic amino acid has been synthesized and evaluated as inhibitors of human platelet aggregation induced by the PAR1 agonist SFLLRN and as cytotoxic agents in human cancer cells. The [...] Read more.
A series of Phe-Gly dipeptide-derived piperazinones containing an aromatic urea moiety and a basic amino acid has been synthesized and evaluated as inhibitors of human platelet aggregation induced by the PAR1 agonist SFLLRN and as cytotoxic agents in human cancer cells. The synthetic strategy involves coupling of a protected basic amino acid benzyl amide to 1,2- and 1,2,4-substituted-piperazinone derivatives, through a carbonylmethyl group at the N1-position, followed by formation of an aromatic urea at the exocyclic moiety linked at the C2 position of the piperazine ring and removal of protecting groups. None of the compounds showed activity in the biological evaluation. Full article
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Open AccessArticle Structural Modeling of Djenkolic Acid with Sulfur Replaced by Selenium and Tellurium
Molecules 2014, 19(4), 4847-4856; doi:10.3390/molecules19044847
Received: 20 February 2014 / Revised: 10 April 2014 / Accepted: 11 April 2014 / Published: 17 April 2014
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Abstract
The comparative structural modeling of djenkolic acid and its derivatives containing selenium and tellurium in chalcogen sites (Ch = Se, Te) has provided detailed information about the bond lengths and bond angles, filling the gap in what we know about the structural [...] Read more.
The comparative structural modeling of djenkolic acid and its derivatives containing selenium and tellurium in chalcogen sites (Ch = Se, Te) has provided detailed information about the bond lengths and bond angles, filling the gap in what we know about the structural characteristics of these aminoacids. The investigation using the molecular mechanics technique with good approximation confirmed the available information on X-ray refinements for the related compounds methionine and selenomethionine, as well as for an estimate made earlier for telluromethionine. It was shown that the Ch-C(3) and Ch-C(4) bond lengths grow in parallel with the increasing anionic radii. Although the distances C-C, C-O, and C-N are very similar, the geometry of conformers is quite different owing to the possibility of rotation about four carbon atoms, hence the remarkable variability observed in dihedral angles. It was shown that the compounds contain a rigid block with two Ch atoms connected through a methylene group. The standard program Gaussian 03 with graphical interface Gaussview 4.1.2 has proved to be satisfactory tool for the structural description of less-common bioactive compositions when direct X-ray results are absent. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Identification of Absorbed Constituents in the Rabbit Plasma and Cerebrospinal Fluid after Intranasal Administration of Asari Radix et Rhizoma by HS-SPME-GC-MS and HPLC-APCI-IT-TOF-MSn
Molecules 2014, 19(4), 4857-4879; doi:10.3390/molecules19044857
Received: 28 January 2014 / Revised: 18 March 2014 / Accepted: 14 April 2014 / Published: 17 April 2014
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Abstract
Traditional Chinese Medicine (TCM) nasal therapy has been utilized to treat numerous diseases for over two millennia. It has many advantages compared with other routes. In this article, headspace-solid phase microextraction-gas chromatography-mass spectrometry and high performance liquid chromatography-atmospheric pressure chemical ionization-ion trap-time [...] Read more.
Traditional Chinese Medicine (TCM) nasal therapy has been utilized to treat numerous diseases for over two millennia. It has many advantages compared with other routes. In this article, headspace-solid phase microextraction-gas chromatography-mass spectrometry and high performance liquid chromatography-atmospheric pressure chemical ionization-ion trap-time of flight-multistage mass spectrometry were applied for the first time to analyze the absorbed constituents in rabbit plasma and cerebrospinal fluid (CSF) after intranasal administration of Asari Radix et Rhizoma (AR). In total, 47 absorbed AR constituents including 14 monoterpenes, 10 phenylpropanoids, four benzene derivatives, two alkanes, nine N-alkylamides and eight lignans were tentatively identified in the rabbit plasma and CSF. Thirty-three absorbed constituents are found to have different bioactivities related to the pharmacological actions of AR through bibliography data retrieval. These indicated that many types of constituents of TCM can be absorbed at the nasal cavity into both rabbit blood and CSF. This is the first study to explore the absorption of AR, and comprehensively analyze the absorbed constituents after intranasal administration of TCM. These findings extend our understanding of the effective substances of AR, and inspire us to make a hypothesis on the mechanism of additive effect of multiple constituents of TCMs, which is very worthy of further investigation. Full article
Open AccessArticle Kinetics of Glycoxidation of Bovine Serum Albumin by Methylglyoxal and Glyoxal and its Prevention by Various Compounds
Molecules 2014, 19(4), 4880-4896; doi:10.3390/molecules19044880
Received: 19 February 2014 / Revised: 9 March 2014 / Accepted: 10 March 2014 / Published: 17 April 2014
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Abstract
The aim of this study was to compare several methods for measurement of bovine serum albumin (BSA) modification by glycoxidation with reactive dicarbonyl compounds (methylglyoxal ‒ MGO and glyoxal ‒ GO), for studies of the kinetics of this process and to compare [...] Read more.
The aim of this study was to compare several methods for measurement of bovine serum albumin (BSA) modification by glycoxidation with reactive dicarbonyl compounds (methylglyoxal ‒ MGO and glyoxal ‒ GO), for studies of the kinetics of this process and to compare the effects of 19 selected compounds on BSA glycation by the aldehydes. The results confirm the higher reactivity of MGO with respect to GO and point to the usefulness of AGE, dityrosine and N′-formylkynurenine fluorescence for monitoring glycation and evaluation of protection against glycation. Different extent of protection against glycation induced by MGO and GO was found for many compounds, probably reflecting effects on various stages of the glycation process. Polyphenols (genistein, naringin and ellagic acid) were found to protect against aldehyde-induced glycation; 1-cyano-4-hydroxycinnamic acid was also an effective protector. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Three New Ring-A Modified Ursane Triterpenes from Davidia involucrata
Molecules 2014, 19(4), 4897-4906; doi:10.3390/molecules19044897
Received: 26 March 2014 / Revised: 10 April 2014 / Accepted: 11 April 2014 / Published: 17 April 2014
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Abstract
Three new ursane triterpenes, 3α,19α-dihydroxy-2-nor-urs-12-en-23,28-dioic acid-23-methyl ester (1), 19α,23-dihydroxy-3-oxo-2-nor-urs-12-en-28-oic acid (2), and 2,3-seco-3-methoxy-3,19α,23-trihydroxy-urs-12-en-2-al-28-oic acid (3), were isolated from the MeOH extract of the branch barks of Davidia involucrata, together with six known compounds. Their structures [...] Read more.
Three new ursane triterpenes, 3α,19α-dihydroxy-2-nor-urs-12-en-23,28-dioic acid-23-methyl ester (1), 19α,23-dihydroxy-3-oxo-2-nor-urs-12-en-28-oic acid (2), and 2,3-seco-3-methoxy-3,19α,23-trihydroxy-urs-12-en-2-al-28-oic acid (3), were isolated from the MeOH extract of the branch barks of Davidia involucrata, together with six known compounds. Their structures were elucidated by means of various spectroscopic analyses. The isolated triterpenes provide important evolutionary and chemotaxonomic knowledge about the monotypic genus Davidia. Five of the identified compounds showed moderate cytotoxicities against the cell proliferation of SGC-7901, MCF-7, and BEL-7404 with IC50 range from 7.26 to 47.41 μM. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Enantioselective Separation of Mirtazapine and Its Metabolites by Capillary Electrophoresis with Acetonitrile Field-Amplified Sample Stacking and Its Application
Molecules 2014, 19(4), 4907-4923; doi:10.3390/molecules19044907
Received: 3 March 2014 / Revised: 10 April 2014 / Accepted: 14 April 2014 / Published: 17 April 2014
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Abstract
A simple, rapid and sensitive chiral capillary zone electrophoresis coupled with acetonitrile-field-amplified sample stacking method was developed that allows the simultaneous enantioselective separation of the mirtazapine, N-demethylmirtazapine, 8-hydroxymirtazapine and mirtazapine-N-oxide. The separation was achieved on an uncoated 40.2 cm × 75 μM [...] Read more.
A simple, rapid and sensitive chiral capillary zone electrophoresis coupled with acetonitrile-field-amplified sample stacking method was developed that allows the simultaneous enantioselective separation of the mirtazapine, N-demethylmirtazapine, 8-hydroxymirtazapine and mirtazapine-N-oxide. The separation was achieved on an uncoated 40.2 cm × 75 μM fused silica capillary with an applied voltage of 16 kV. The electrophoretic analyses were carried out in 6.25 mM borate–25 mM phosphate solution at pH 2.8 containing 5.5 mg/mL carboxymethyl-β-cyclodextrin. The detection wavelength was 200 nm. Under these optimized conditions, satisfactory chiral separations of four pair enantiomers were achieved in less than 7 min in vitro. After one step clean-up liquid-liquid extraction using 96-well format, sample was introduced capillary zone electrophoresis with acetonitrile-field-amplified sample stacking to enhance the sensitivity of enantiomers. The method was validated with respect to specificity, linearity, lower limit of quantitation, accuracy, precision, extraction recovery and stability. The lower limit of quantification was 0.5 ng/mL with linear response over the 0.5–50 ng/mL concentration range for each mirtazapine, N-demethylmirtazapine and 8-hydroxymirtazapine enantiomer. The developed and validated method has been successfully applied to the enantioselective pharmacokinetic studies in 12 healthy volunteers after oral administration of rac- mirtazapine. Full article
Open AccessArticle The Synergistic Biologic Activity of Oleanolic and Ursolic Acids in Complex with Hydroxypropyl-γ-Cyclodextrin
Molecules 2014, 19(4), 4924-4940; doi:10.3390/molecules19044924
Received: 4 March 2014 / Revised: 4 April 2014 / Accepted: 9 April 2014 / Published: 17 April 2014
Cited by 16 | PDF Full-text (851 KB) | HTML Full-text | XML Full-text
Abstract
Oleanolic and ursolic acids are natural triterpenic compounds with pentacyclic cholesterol-like structures which gives them very low water solubility, a significant disadvantage in terms of bioavailability. We previously reported the synthesis of inclusion complexes between these acids and cyclodextrins, as well as [...] Read more.
Oleanolic and ursolic acids are natural triterpenic compounds with pentacyclic cholesterol-like structures which gives them very low water solubility, a significant disadvantage in terms of bioavailability. We previously reported the synthesis of inclusion complexes between these acids and cyclodextrins, as well as their in vivo evaluation on chemically induced skin cancer experimental models. In this study the synergistic activity of the acid mixture included inside hydroxypropyl-gamma-cyclodextrin (HPGCD) was monitored using in vitro tests and in vivo skin cancer models. The coefficient of drug interaction (CDI) was used to characterize the interactions as synergism, additivity or antagonism. Our results revealed an increased antitumor activity for the mixture of the two triterpenic acids, both single and in complex with cyclodextrin, thus proving their complementary biologic activities. Full article
Open AccessArticle Anti-Proliferative and Apoptosis-Inducing Effects of Camptothecin-20(s)-O-(2-pyrazolyl-1)acetic Ester in Human Breast Tumor MCF-7 Cells
Molecules 2014, 19(4), 4941-4955; doi:10.3390/molecules19044941
Received: 22 January 2014 / Revised: 2 April 2014 / Accepted: 3 April 2014 / Published: 17 April 2014
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Abstract
Camptothecin-20(s)-O-(2-pyrazolyl-1)acetic ester (CPT6) is a novel semi-synthetic analog of camptothecin. In a previous report, CPT6 possessed higher cytotoxic activity in vitro towards human breast tumor MCF-7 cells than topotecan. In this study, the antitumor activity of CPT6 on the human [...] Read more.
Camptothecin-20(s)-O-(2-pyrazolyl-1)acetic ester (CPT6) is a novel semi-synthetic analog of camptothecin. In a previous report, CPT6 possessed higher cytotoxic activity in vitro towards human breast tumor MCF-7 cells than topotecan. In this study, the antitumor activity of CPT6 on the human breast tumor MCF-7 cell line was analyzed using the MTT method. The underlying mechanism of CPT6 action was investigated by analyzing the cell cycle distribution, apoptotic proportion, changes in mitochondrial membrane potential, and intracellular Ca2+ concentration using flow cytometry. Nuclear and mitochondrial morphologies were also observed by laser scanning confocal and transmission electron microscopy. DNA damage was observed in MCF-7 cells treated with CPT6. Low-dose CPT6 had a significant cytotoxic effect and could inhibit proliferation and induce apoptosis in MCF-7 cells, possibly through cell nucleus fragmentation and DNA damage. CPT6 thus appears to display potent antitumor activity against human breast tumor MCF-7 cells via the induction of apoptosis, and may be a useful alternative drug for breast cancer therapy. Full article
(This article belongs to the Section Medicinal Chemistry)
Open AccessArticle Characterization of Natural Aryl Hydrocarbon Receptor Agonists from Cassia Seed and Rosemary
Molecules 2014, 19(4), 4956-4966; doi:10.3390/molecules19044956
Received: 8 February 2014 / Revised: 14 April 2014 / Accepted: 15 April 2014 / Published: 17 April 2014
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Abstract
Many recent studies have suggested that activation of the aryl hydrocarbon receptor (AhR) reduces immune responses, thus suppressing allergies and autoimmune diseases. In our continuing study on natural AhR agonists in foods, we examined the influence of 37 health food materials on [...] Read more.
Many recent studies have suggested that activation of the aryl hydrocarbon receptor (AhR) reduces immune responses, thus suppressing allergies and autoimmune diseases. In our continuing study on natural AhR agonists in foods, we examined the influence of 37 health food materials on the AhR using a reporter gene assay, and found that aqueous ethanol extracts of cassia seed and rosemary had particularly high AhR activity. To characterize the AhR-activating substances in these samples, the chemical constituents of the respective extracts were identified. From an active ethyl acetate fraction of the cassia seed extract, eight aromatic compounds were isolated. Among these compounds, aurantio-obtusin, an anthraquinone, elicited marked AhR activation. Chromatographic separation of an active ethyl acetate fraction of the rosemary extract gave nine compounds. Among these compounds, cirsimaritin induced AhR activity at 10–102 μM, and nepitrin and homoplantagenin, which are flavone glucosides, showed marked AhR activation at 10–103 μM. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Microsomal Prostaglandin E Synthase-1 Deficiency Exacerbates Pulmonary Fibrosis Induced by Bleomycin in Mice
Molecules 2014, 19(4), 4967-4985; doi:10.3390/molecules19044967
Received: 24 February 2014 / Revised: 8 April 2014 / Accepted: 11 April 2014 / Published: 21 April 2014
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Abstract
Microsomal prostaglandin E2 synthase-1 (mPGES-1), an inducible enzyme that converts prostaglandin H2 (PGH2) to prostaglandin E2 (PGE2), plays an important role in a variety of diseases. So far, the role of mPGES-1 in idiopathic pulmonary fibrosis (IPF) remained [...] Read more.
Microsomal prostaglandin E2 synthase-1 (mPGES-1), an inducible enzyme that converts prostaglandin H2 (PGH2) to prostaglandin E2 (PGE2), plays an important role in a variety of diseases. So far, the role of mPGES-1 in idiopathic pulmonary fibrosis (IPF) remained unknown. The current study aimed to investigate the role of mPGES-1 in pulmonary fibrosis induced by bleomycin in mice. We found that mPGES-1 deficient (mPGES-1/−) mice exhibited more severe fibrotic lesions with a decrease in PGE2 content in lungs after bleomycin treatment when compared with wild type (mPGES-1+/+) mice. The mPGES-1 expression levels and PGE2 content were also decreased in bleomycin-treated mPGES-1+/+ mice compared to saline-treated mPGES-1+/+ mice. Moreover, in both mPGES-1/− and mPGES-1+/+ mice, bleomycin treatment reduced the expression levels of E prostanoid receptor 2 (EP2) and EP4 receptor in lungs, whereas had little effect on EP1 and EP3. In cultured human lung fibroblast cells (MRC-5), siRNA-mediated knockdown of mPGES-1 augmented transforming growth factor-β1 (TGF-β1)-induced α-smooth muscle actin (α-SMA) protein expression, and the increase was reversed by treatment of PGE2, selective EP2 agonist and focal adhesion kinase (FAK) inhibitor. In conclusion, these findings revealed mPGES-1 exerts an essential effect against pulmonary fibrogenesis via EP2-mediated signaling transduction, and activation of mPGES-1-PGE2-EP2-FAK signaling pathway may represent a new therapeutic strategy for treatment of IPF patients. Full article
Open AccessArticle High Efficiency Acetylcholinesterase Immobilization on DNA Aptamer Modified Surfaces
Molecules 2014, 19(4), 4986-4996; doi:10.3390/molecules19044986
Received: 26 February 2014 / Revised: 8 April 2014 / Accepted: 11 April 2014 / Published: 21 April 2014
Cited by 5 | PDF Full-text (629 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
We report here the in vitro selection of DNA aptamers for electric eel acetylcholinesterase (AChE). One selected aptamer sequence (R15/19) has a high affinity towards the enzyme (Kd = 157 ± 42 pM). Characterization of the aptamer showed its binding is [...] Read more.
We report here the in vitro selection of DNA aptamers for electric eel acetylcholinesterase (AChE). One selected aptamer sequence (R15/19) has a high affinity towards the enzyme (Kd = 157 ± 42 pM). Characterization of the aptamer showed its binding is not affected by low ionic strength (~20 mM), however significant reduction in affinity occurred at high ionic strength (~1.2 M). In addition, this aptamer does not inhibit the catalytic activity of AChE that we exploit through immobilization of the DNA on a streptavidin-coated surface. Subsequent immobilization of AChE by the aptamer results in a 4-fold higher catalytic activity when compared to adsorption directly on to plastic. Full article
(This article belongs to the Section Molecular Diversity)
Open AccessArticle Surface-Functionalized Hyperbranched Poly(Amido Acid) Magnetic Nanocarriers for Covalent Immobilization of a Bacterial γ-Glutamyltranspeptidase
Molecules 2014, 19(4), 4997-5012; doi:10.3390/molecules19044997
Received: 11 March 2014 / Revised: 15 April 2014 / Accepted: 17 April 2014 / Published: 22 April 2014
Cited by 9 | PDF Full-text (2201 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In this study, we synthesized water-soluble hyperbranched poly(amido acid)s (HBPAAs) featuring multiple terminal CO2H units and internal tertiary amino and amido moieties and then used them in conjunction with an in situ Fe2+/Fe3+ co-precipitation process to prepare [...] Read more.
In this study, we synthesized water-soluble hyperbranched poly(amido acid)s (HBPAAs) featuring multiple terminal CO2H units and internal tertiary amino and amido moieties and then used them in conjunction with an in situ Fe2+/Fe3+ co-precipitation process to prepare organic/magnetic nanocarriers comprising uniformly small magnetic iron oxide nanoparticles (NP) incorporated within the globular HBPAAs. Transmission electron microscopy revealed that the HBPAA-γ-Fe2O3 NPs had dimensions of 6–11 nm, significantly smaller than those of the pristine γ-Fe2O3 (20–30 nm). Subsequently, we covalently immobilized a bacterial γ-glutamyltranspeptidase (BlGGT) upon the HBPAA-γ-Fe2O3 nanocarriers through the formation of amide linkages in the presence of a coupling agent. Magnetization curves of the HBPAA-γ-Fe2O3/BlGGT composites measured at 300 K suggested superparamagnetic characteristics, with a saturation magnetization of 52 emu g−1. The loading capacity of BlGGT on the HBPAA-γ-Fe2O3 nanocarriers was 16 mg g−1 support; this sample provided a 48% recovery of the initial activity. The immobilized enzyme could be recycled 10 times with 32% retention of the initial activity; it had stability comparable with that of the free enzyme during a storage period of 63 days. The covalent immobilization and stability of the enzyme and the magnetization provided by the HBPAA-γ-Fe2O3 NPs suggests that this approach could be an economical means of depositing bioactive enzymes upon nanocarriers for BlGGT-mediated bio-catalysis. Full article
(This article belongs to the Special Issue Enzyme Immobilization)
Open AccessArticle Biocompatible Fe3O4 Increases the Efficacy of Amoxicillin Delivery against Gram-Positive and Gram-Negative Bacteria
Molecules 2014, 19(4), 5013-5027; doi:10.3390/molecules19045013
Received: 5 March 2014 / Revised: 9 April 2014 / Accepted: 14 April 2014 / Published: 22 April 2014
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Abstract
This paper reports the synthesis and characterization of amoxicillin- functionalized magnetite nanostructures (Fe3O4@AMO), revealing and discussing several biomedical applications of these nanomaterials. Our results proved that 10 nm Fe3O4@AMO nanoparticles does not alter the [...] Read more.
This paper reports the synthesis and characterization of amoxicillin- functionalized magnetite nanostructures (Fe3O4@AMO), revealing and discussing several biomedical applications of these nanomaterials. Our results proved that 10 nm Fe3O4@AMO nanoparticles does not alter the normal cell cycle progression of cultured diploid cells, and an in vivo murine model confirms that the nanostructures disperse through the host body and tend to localize in particular sites and organs. The nanoparticles were found clustered especially in the lungs, kidneys and spleen, next to the blood vessels at this level, while being totally absent in the brain and liver, suggesting that they are circulated through the blood flow and have low toxicity. Fe3O4@AMO has the ability to be easily circulated through the body and optimizations may be done so these nanostructures cluster to a specific target region. Functionalized magnetite nanostructures proved a great antimicrobial effect, being active against both the Gram positive pathogen S. aureus and the Gram negative pathogen E. coli. The fabricated nanostructures significantly reduced the minimum inhibitory concentration (MIC) of the active drug. This result has a great practical relevance, since the functionalized nanostructures may be used for decreasing the therapeutic doses which usually manifest great severe side effects, when administrated in high doses. Fe3O4@AMO represents also a suitable approach for the development of new alternative strategies for improving the activity of therapeutic agents by targeted delivery and controlled release. Full article
(This article belongs to the Special Issue Bio and Nanomaterials Based on Fe3O4)
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Open AccessCommunication C5-Azobenzene-substituted 2'-Deoxyuridine-containing Oligodeoxynucleotides for Photo-Switching Hybridization
Molecules 2014, 19(4), 5109-5118; doi:10.3390/molecules19045109
Received: 3 March 2014 / Revised: 15 April 2014 / Accepted: 17 April 2014 / Published: 22 April 2014
Cited by 6 | PDF Full-text (581 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A new photoisomeric nucleoside dUAz bearing an azobenzene group at the C5-position of 2'-deoxyuridine was designed and synthesized. Photoisomerization of dUAz in oligodeoxynucleotides can be achieved rapidly and selectively with 365 nm (forward) and 450 nm (backward) irradiation. Thermal denaturation [...] Read more.
A new photoisomeric nucleoside dUAz bearing an azobenzene group at the C5-position of 2'-deoxyuridine was designed and synthesized. Photoisomerization of dUAz in oligodeoxynucleotides can be achieved rapidly and selectively with 365 nm (forward) and 450 nm (backward) irradiation. Thermal denaturation experiments revealed that dUAz stabilized the duplex in the cis-form and destabilized it in the trans-form with mismatch discrimination ability comparable to thymidine. These results indicate that dUAz could be a powerful material for reversibly manipulating nucleic acid hybridization with spatiotemporal control. Full article
(This article belongs to the Special Issue Molecular Switches)
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Open AccessArticle Catechins and Procyanidins of Ginkgo biloba Show Potent Activities towards the Inhibition of β-Amyloid Peptide Aggregation and Destabilization of Preformed Fibrils
Molecules 2014, 19(4), 5119-5134; doi:10.3390/molecules19045119
Received: 21 March 2014 / Revised: 9 April 2014 / Accepted: 10 April 2014 / Published: 22 April 2014
Cited by 8 | PDF Full-text (449 KB) | HTML Full-text | XML Full-text
Abstract
Catechins and procyanidins, together with flavonoid glycosides and terpene trilactones, are three important categories of components in the standard extract of Ginkgo biloba leaves (EGb761). In this research, catechins and proanthocyanidins were found to exist in both the extract of Ginkgo leaves [...] Read more.
Catechins and procyanidins, together with flavonoid glycosides and terpene trilactones, are three important categories of components in the standard extract of Ginkgo biloba leaves (EGb761). In this research, catechins and proanthocyanidins were found to exist in both the extract of Ginkgo leaves and Ginkgo products. By comparing with reference compounds, six of them were identified as (+)-catechin, (−)-epicatechin, (−)-gallocatechin, (−)-epigallocatechin and procyanidins B1 and B3. The activities of these polyphenols in the inhibition of Aβ42 aggregation and the destabilization of preformed fibrils were evaluated using biochemical assays, which showed that all six of the polyphenols, as well as a fraction of the extract of Ginkgo biloba leaves (EGb) containing catechins and procyanidins, exerted potent inhibitory activities towards Aβ42 aggregation and could also destabilize the performed fibrils. Catechins and procyanidins can therefore be regarded as the potent active constituents of EGb761 in terms of their inhibition of Aβ42 aggregation and destabilization of the fibrils. Although quantitative mass spectroscopic analysis revealed that the catechins and procyanidins are only present in low concentrations in EGb761, these components should be studied in greater detail because of their potent inhibitory effects towards Aβ42 aggregation and their ability to destabilize preformed fibrils, especially during the quality control of Ginkgo leaves and the manufacture of Ginkgo products. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle The Effect of DA-9701 on 5-Hydroxytryptamine-Induced Contraction of Feline Esophageal Smooth Muscle Cells
Molecules 2014, 19(4), 5135-5149; doi:10.3390/molecules19045135
Received: 7 February 2014 / Revised: 8 April 2014 / Accepted: 15 April 2014 / Published: 22 April 2014
Cited by 6 | PDF Full-text (696 KB) | HTML Full-text | XML Full-text
Abstract
Serotonin, or 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter found in blood platelets, the gastrointestinal (GI) tract, and the central nervous system (CNS) of animals and humans. The signaling pathways of 5-hydroxytryptamine (5-HT)-induced contractions in cat esophageal smooth muscle cell (ESMC)s have been [...] Read more.
Serotonin, or 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter found in blood platelets, the gastrointestinal (GI) tract, and the central nervous system (CNS) of animals and humans. The signaling pathways of 5-hydroxytryptamine (5-HT)-induced contractions in cat esophageal smooth muscle cell (ESMC)s have been identified, but the downstream components of the 5-HT signaling pathway remain unclear. DA-9701 is the standardized extract of the Pharbitis nil Choisy seed (Pharbitidis Semen, Convolvulaceae) and the root of Corydalis yahusuo W.T. Wang (Corydalis Tuber, Papaveraceae). DA-9701 is known to have strong gastroprokinetic effects and a good safety profile. In this study, we investigated the 5-HT signaling pathway at the G-protein level, and we explored the mechanisms by which DA-9701 induces smooth muscle contraction. Freshly isolated smooth muscle cells were harvested from the feline esophagus, and cells were permeabilized to measure their length. 5-HT produced esophageal smooth muscle contractions in a dose-dependent manner. Furthermore, 5-HT produced a relatively long-acting contraction. 5-HT binds to the 5-HT2, 5-HT3 and 5-HT4 receptors to induce smooth muscle contraction in feline ESMCs. These receptors, which are located in esophageal smooth muscle, are coupled to Gαq, Gαo and Gαs. These G proteins activate PLC, which leads to Ca2+/calmodulin-dependent MLCK activation, resulting in MLC20 phosphorylation and cell contraction. Conversely, DA-9701 inhibits 5-HT-induced contraction by inhibiting MLC20 phosphorylation. Full article
Open AccessArticle Development of Simple Sequence Repeat (SSR) Markers of Sesame (Sesamum indicum) from a Genome Survey
Molecules 2014, 19(4), 5150-5162; doi:10.3390/molecules19045150
Received: 17 February 2014 / Revised: 31 March 2014 / Accepted: 14 April 2014 / Published: 22 April 2014
Cited by 11 | PDF Full-text (340 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Sesame (Sesamum indicum), an important oil crop, is widely grown in tropical and subtropical regions. It provides part of the daily edible oil allowance for almost half of the world’s population. A limited number of co-dominant markers has been developed [...] Read more.
Sesame (Sesamum indicum), an important oil crop, is widely grown in tropical and subtropical regions. It provides part of the daily edible oil allowance for almost half of the world’s population. A limited number of co-dominant markers has been developed and applied in sesame genetic diversity and germplasm identity studies. Here we report for the first time a whole genome survey used to develop simple sequence repeat (SSR) markers and to detect the genetic diversity of sesame germplasm. From the initial assembled sesame genome, 23,438 SSRs (≥5 repeats) were identified. The most common repeat motif was dinucleotide with a frequency of 84.24%, followed by 13.53% trinucleotide, 1.65% tetranucleotide, 0.3% pentanucleotide and 0.28% hexanucleotide motifs. From 1500 designed and synthesised primer pairs, 218 polymorphic SSRs were developed and used to screen 31 sesame accessions that from 12 countries. STRUCTURE and phylogenetic analyses indicated that all sesame accessions could be divided into two groups: one mainly from China and another from other countries. Cluster analysis classified Chinese major sesame varieties into three groups. These novel SSR markers are a useful tool for genetic linkage map construction, genetic diversity detection, and marker-assisted selective sesame breeding. Full article
(This article belongs to the Section Molecular Diversity)
Open AccessArticle Antioxidant and Antitumor Activities of New Synthesized Aromatic C-Nucleoside Derivatives
Molecules 2014, 19(4), 5163-5190; doi:10.3390/molecules19045163
Received: 6 March 2014 / Revised: 9 April 2014 / Accepted: 14 April 2014 / Published: 22 April 2014
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Abstract
The carbohydrazide 1 was used as the precursor for the synthesis of a number of new aromatic C-nucleosides containing 1,3,4-oxadiazole 7, [1,3,4]oxadiazolo[2,3-a]isoindole 10b and pyrazole units 18. On the other hand, the thiosemicarbazone 20 was used as the key [...] Read more.
The carbohydrazide 1 was used as the precursor for the synthesis of a number of new aromatic C-nucleosides containing 1,3,4-oxadiazole 7, [1,3,4]oxadiazolo[2,3-a]isoindole 10b and pyrazole units 18. On the other hand, the thiosemicarbazone 20 was used as the key intermediate for synthesis of 1,3,4-oxadiazole  and 1,2,4-triazole-3-thione derivatives 21 and 23. The antioxidant activities of the prepared compounds were evaluated. The carbohydrazide 1 in particular was found to have potent antioxidant and antitumor activity. Full article
Open AccessArticle Anti-Amoebic Properties of Carbonyl Thiourea Derivatives
Molecules 2014, 19(4), 5191-5204; doi:10.3390/molecules19045191
Received: 26 November 2013 / Revised: 25 March 2014 / Accepted: 9 April 2014 / Published: 22 April 2014
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Abstract
Thiourea derivatives display a broad spectrum of applications in chemistry, various industries, medicines and various other fields. Recently, different thiourea derivatives have been synthesized and explored for their anti-microbial properties. In this study, four carbonyl thiourea derivatives were synthesized and characterized, and [...] Read more.
Thiourea derivatives display a broad spectrum of applications in chemistry, various industries, medicines and various other fields. Recently, different thiourea derivatives have been synthesized and explored for their anti-microbial properties. In this study, four carbonyl thiourea derivatives were synthesized and characterized, and then further tested for their anti-amoebic properties on two potential pathogenic species of Acanthamoeba, namely A. castellanii (CCAP 1501/2A) and A. polyphaga (CCAP 1501/3A). The results indicate that these newly-synthesized thiourea derivatives are active against both Acanthamoeba species. The IC50 values obtained were in the range of 2.39–8.77 µg·mL‑1 (9.47–30.46 µM) for A. castellanii and 3.74–9.30 µg·mL‑1 (14.84–31.91 µM) for A. polyphaga. Observations on the amoeba morphology indicated that the compounds caused the reduction of the amoeba size, shortening of their acanthopodia structures, and gave no distinct vacuolar and nuclear structures in the amoeba cells. Meanwhile, fluorescence microscopic observation using acridine orange and propidium iodide (AOPI) staining revealed that the synthesized compounds induced compromised-membrane in the amoeba cells. The results of this study proved that these new carbonyl thiourea derivatives, especially compounds M1 and M2 provide potent cytotoxic properties toward pathogenic Acanthamoeba to suggest that they can be developed as new anti-amoebic agents for the treatment of Acanthamoeba keratitis. Full article
Open AccessArticle A Benzoic Acid Derivative and Flavokawains from Piper species as Schistosomiasis Vector Controls
Molecules 2014, 19(4), 5205-5218; doi:10.3390/molecules19045205
Received: 11 March 2014 / Revised: 11 April 2014 / Accepted: 15 April 2014 / Published: 23 April 2014
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Abstract
The search of alternative compounds to control tropical diseases such as schistosomiasis has pointed to secondary metabolites derived from natural sources. Piper species are candidates in strategies to control the transmission of schistosomiasis due to their production of molluscicidal compounds. A new [...] Read more.
The search of alternative compounds to control tropical diseases such as schistosomiasis has pointed to secondary metabolites derived from natural sources. Piper species are candidates in strategies to control the transmission of schistosomiasis due to their production of molluscicidal compounds. A new benzoic acid derivative and three flavokawains from Piper diospyrifolium, P. cumanense and P. gaudichaudianum displayed significant activities against Biomphalaria glabrata snails. Additionally, “in silico” studies were performed using docking assays and Molecular Interaction Fields to evaluate the physical-chemical differences among the compounds in order to characterize the observed activities of the test compounds against Biomphalaria glabrata snails. Full article
Open AccessArticle Bioactivity of a Family of Chiral Nonracemic Aminobenzylnaphthols towards Candida albicans
Molecules 2014, 19(4), 5219-5230; doi:10.3390/molecules19045219
Received: 20 February 2014 / Revised: 8 April 2014 / Accepted: 16 April 2014 / Published: 23 April 2014
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Abstract
Chiral nonracemic aminobenzylnaphthols were obtained by a Betti multi-component reaction between 2-naphthol, aryl aldehydes and enantiopure arylethylamine. Moreover, some new aminobenzylnaphthols were synthesized by a similar reaction between 2-naphthol, aryl aldehydes and prolinol. These aminobenzylnaphthols, synthesized from different components and thus having [...] Read more.
Chiral nonracemic aminobenzylnaphthols were obtained by a Betti multi-component reaction between 2-naphthol, aryl aldehydes and enantiopure arylethylamine. Moreover, some new aminobenzylnaphthols were synthesized by a similar reaction between 2-naphthol, aryl aldehydes and prolinol. These aminobenzylnaphthols, synthesized from different components and thus having different structural features, were tested as anti-yeast agents inhibiting Candida albicans. The effect towards the test strain was studied with a microdilution approach and three different concentrations (150, 300 and 450 µg/mL) were tested. The best results were found for the aminobenzylnaphthols obtained from 1-naphthylethylamine and from natural prolinol. The use of the two-way ANOVA highlighted the better performances of the prolinol derivative among the differently structured aminobenzylnaphthols that were screened. The activity towards C. albicans of this prolinol derivative resulted to be interesting and could represent a promising alternative to overcome the problem of the strains resistant to the traditional antifungals. Full article
(This article belongs to the Special Issue Parallel Synthesis)
Open AccessArticle The Intramolecular Diels-Alder Reaction of Diarylheptanoids — Quantum Chemical Calculation of Structural Features Favoring the Formation of Phenylphenalenones
Molecules 2014, 19(4), 5231-5242; doi:10.3390/molecules19045231
Received: 21 January 2014 / Revised: 15 April 2014 / Accepted: 17 April 2014 / Published: 23 April 2014
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Abstract
Diarylheptanoids have been reported as biosynthetic precursors of phenylphenalenones in plants. Quantum chemical calculations of molecular geometry and orbitals were used to elaborate which structural features are required to determine if diarylheptanoids can undergo an intramolecular Diel-Alder reaction to form phenylphenalenones. The [...] Read more.
Diarylheptanoids have been reported as biosynthetic precursors of phenylphenalenones in plants. Quantum chemical calculations of molecular geometry and orbitals were used to elaborate which structural features are required to determine if diarylheptanoids can undergo an intramolecular Diel-Alder reaction to form phenylphenalenones. The computational data showed that an ortho-quinone- or a hydoxyketone-bearing ring A, containing the dienophile moiety, and a heptadiene chain with conjugated cisoid double bonds at C-4/C-6 and a saturated segment consisting of two sp3-carbon atoms, are required. Only four diarylheptanoids out of eighteen studied compounds proved to be suitable candidates. Among them are two 3,5-dideoxy compounds and two other compounds oxygenated only at C-3, suggesting that lachnanthocarpone, a representative of the 6-oxygenated phenylphenalenones, and anigorufone, a representative of the 6-deoxy phenylphenalenones, are not connected via a precursor-product relationship (“late reduction at C-6”) but formed through partially separate pathways. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Integrated Computational Tools for Identification of CCR5 Antagonists as Potential HIV-1 Entry Inhibitors: Homology Modeling, Virtual Screening, Molecular Dynamics Simulations and 3D QSAR Analysis
Molecules 2014, 19(4), 5243-5265; doi:10.3390/molecules19045243
Received: 27 January 2014 / Revised: 1 April 2014 / Accepted: 9 April 2014 / Published: 23 April 2014
Cited by 5 | PDF Full-text (2801 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Using integrated in-silico computational techniques, including homology modeling, structure-based and pharmacophore-based virtual screening, molecular dynamic simulations, per-residue energy decomposition analysis and atom-based 3D-QSAR analysis, we proposed ten novel compounds as potential CCR5-dependent HIV-1 entry inhibitors. Via validated docking calculations, binding free energies [...] Read more.
Using integrated in-silico computational techniques, including homology modeling, structure-based and pharmacophore-based virtual screening, molecular dynamic simulations, per-residue energy decomposition analysis and atom-based 3D-QSAR analysis, we proposed ten novel compounds as potential CCR5-dependent HIV-1 entry inhibitors. Via validated docking calculations, binding free energies revealed that novel leads demonstrated better binding affinities with CCR5 compared to maraviroc, an FDA-approved HIV-1 entry inhibitor and in clinical use. Per-residue interaction energy decomposition analysis on the averaged MD structure showed that hydrophobic active residues Trp86, Tyr89 and Tyr108 contributed the most to inhibitor binding. The validated 3D-QSAR model showed a high cross-validated rcv2 value of 0.84 using three principal components and non-cross-validated r2 value of 0.941. It was also revealed that almost all compounds in the test set and training set yielded a good predicted value. Information gained from this study could shed light on the activity of a new series of lead compounds as potential HIV entry inhibitors and serve as a powerful tool in the drug design and development machinery. Full article
(This article belongs to the Special Issue In-Silico Drug Design and In-Silico Screening)
Open AccessArticle Immunostimulatory Effects of Polysaccharides Isolated from Makgeolli (Traditional Korean Rice Wine)
Molecules 2014, 19(4), 5266-5277; doi:10.3390/molecules19045266
Received: 19 February 2014 / Revised: 25 March 2014 / Accepted: 18 April 2014 / Published: 23 April 2014
Cited by 8 | PDF Full-text (333 KB) | HTML Full-text | XML Full-text
Abstract
Makgeolli is a traditional Korean rice wine, reported to have various biological functions. In this study, the immunostimulatory activity of a polysaccharide from makgeolli (PSM) was investigated. The polysaccharide fraction was isolated from makgeolli by hot water extraction, ethanol precipitation, dialysis, and [...] Read more.
Makgeolli is a traditional Korean rice wine, reported to have various biological functions. In this study, the immunostimulatory activity of a polysaccharide from makgeolli (PSM) was investigated. The polysaccharide fraction was isolated from makgeolli by hot water extraction, ethanol precipitation, dialysis, and lyophilization. The major constituents in PSM were neutral sugars (87.3%). PSM was composed of five different sugars, glucose, mannose, galactose, xylose, and arabinose. In normal mice, PSM treatment increased the spleen index (p < 0.05) as well as splenocyte proliferation (p < 0.05) in combination with concanavalin A or lipopolysaccharide. The immunostimulatory activities of PSM were also examined in cyclophosphamide (CY)-induced immunosuppressed mice. Mice treated with PSM exhibited increased splenocyte proliferation (p < 0.05), natural killer cell activity, and white blood cell counts (p < 0.01) compared with immunosuppressed mice. These results indicate that PSM can enhance immune function in normal mice and CY-induced immunosuppressed mice. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Thermodynamics and Kinetics of Guest-Induced Switching between “Basket Handle” Porphyrin Isomers
Molecules 2014, 19(4), 5278-5300; doi:10.3390/molecules19045278
Received: 10 March 2014 / Revised: 14 April 2014 / Accepted: 17 April 2014 / Published: 23 April 2014
Cited by 1 | PDF Full-text (1396 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The synthesis and switching properties of two “basket handle” porphyrin isomers is described. The cis-oriented meso-phenyl groups of these porphyrins are linked at their ortho-positons via benzocrown-ether-based spacers, which as a result of slow atropisomerization are located either on [...] Read more.
The synthesis and switching properties of two “basket handle” porphyrin isomers is described. The cis-oriented meso-phenyl groups of these porphyrins are linked at their ortho-positons via benzocrown-ether-based spacers, which as a result of slow atropisomerization are located either on the same side of the porphyrin plane (cis), or on opposite sides (trans). In solution, the cis-linked isomer slowly isomerizes in the direction of the thermodynamically more stable trans-isomer. In the presence of viologen (N,N'-dialkyl-4,4'-bipyridinium) derivatives, which have different affinities for the two isomers, the isomerization equilibrium could be significantly influenced. In addition, the presence of these guests was found to enhance the rate of the switching process, which was suggested to be caused by favorable interactions between the positively charged guest and the crown ethers of the receptor, stabilizing the transition state energies of the isomerization reaction between the two isomers. Full article
(This article belongs to the Special Issue Molecular Switches)
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Open AccessArticle Identifying Stereoisomers by ab-initio Calculation of Secondary Isotope Shifts on NMR Chemical Shieldings
Molecules 2014, 19(4), 5301-5312; doi:10.3390/molecules19045301
Received: 27 February 2014 / Revised: 8 April 2014 / Accepted: 11 April 2014 / Published: 23 April 2014
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Abstract
We present ab-initio calculations of secondary isotope effects on NMR chemical shieldings. The change of the NMR chemical shift of a certain nucleus that is observed if another nucleus is replaced by a different isotope can be calculated by computing vibrational corrections [...] Read more.
We present ab-initio calculations of secondary isotope effects on NMR chemical shieldings. The change of the NMR chemical shift of a certain nucleus that is observed if another nucleus is replaced by a different isotope can be calculated by computing vibrational corrections on the NMR parameters using electronic structure methods. We demonstrate that the accuracy of the computational results is sufficient to even distinguish different conformers. For this purpose, benchmark calculations for fluoro(2-2H)ethane in gauche and antiperiplanar conformation are carried out at the HF, MP2 and CCSD(T) level of theory using basis sets ranging from double- to quadruple-zeta quality. The methodology is applied to the secondary isotope shifts for 2-fluoronorbornane in order to resolve an ambiguity in the literature on the assignment of endo- and exo-2-fluoronorbornanes with deuterium substituents in endo-3 and exo-3 positions, also yielding insight into mechanistic details of the corresponding synthesis. Full article
(This article belongs to the Special Issue Isotope Effects)
Open AccessArticle Synthesis, Crystal Structure, Spectra and Quantum Chemical Study on 1-Phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline
Molecules 2014, 19(4), 5313-5324; doi:10.3390/molecules19045313
Received: 24 March 2014 / Revised: 14 April 2014 / Accepted: 17 April 2014 / Published: 23 April 2014
PDF Full-text (897 KB) | HTML Full-text | XML Full-text
Abstract
1-Phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. UV-Vis spectra and fluorescence spectra were measured. Density functional theory calculations on the structure of the title compound were performed at the B3LYP/6-311G** level of theory. NPA atomic [...] Read more.
1-Phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. UV-Vis spectra and fluorescence spectra were measured. Density functional theory calculations on the structure of the title compound were performed at the B3LYP/6-311G** level of theory. NPA atomic charge distributions indicate that, although the S atom in the thienyl ring loses coordination capacity, the title compound still may be used as a potential multi-dentate ligand to coordinate with metallic ions. The calculation of the second order optical nonlinearity was carried out. Natural bond orbital analyses indicate that the electronic absorption bands are mainly derived from the contribution of n π* and π π* transitions. Fluorescence spectra determination shows that the title compound is a potential orange-light emitting material. Full article
Open AccessArticle Rice Bran Feruloylated Oligosaccharides Activate Dendritic Cells via Toll-Like Receptor 2 and 4 Signaling
Molecules 2014, 19(4), 5325-5347; doi:10.3390/molecules19045325
Received: 29 January 2014 / Revised: 29 March 2014 / Accepted: 31 March 2014 / Published: 23 April 2014
Cited by 5 | PDF Full-text (2166 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
This work presents the effects of feruloylated oligosaccharides (FOs) of rice bran on murine bone marrow-derived dendritic cells (BMDCs) and the potential pathway through which the effects are mediated. We found that FOs induced phenotypic maturation of DCs, as shown by the [...] Read more.
This work presents the effects of feruloylated oligosaccharides (FOs) of rice bran on murine bone marrow-derived dendritic cells (BMDCs) and the potential pathway through which the effects are mediated. We found that FOs induced phenotypic maturation of DCs, as shown by the increased expression of CD40, CD80/CD86 and MHC-I/II molecules. FOs efficiently induced maturation of DCs generated from C3H/HeN or C57BL/6 mice with normal toll-like receptor 4 (TLR-4) or TLR-2 but not DCs from mice with mutated TLR4 or TLR2. The mechanism of action of FOs may be mediated by increased phosphorylation of ERK, p38 and JNK mitogen-activated protein kinase (MAPKs) and increased NF-kB activity, which are important signaling molecules downstream of TLR-4 and TLR-2. These data suggest that FOs induce DCs maturation through TLR-4 and/or TLR-2 and that FOs might have potential efficacy against tumor or virus infection or represent a candidate-adjuvant approach for application in immunotherapy and vaccination. Full article
(This article belongs to the Section Natural Products)
Open AccessArticle Effect of High Pressure Microfluidization on the Crystallization Behavior of Palm Stearin — Palm Olein Blends
Molecules 2014, 19(4), 5348-5359; doi:10.3390/molecules19045348
Received: 3 February 2014 / Revised: 13 April 2014 / Accepted: 21 April 2014 / Published: 24 April 2014
Cited by 2 | PDF Full-text (2595 KB) | HTML Full-text | XML Full-text
Abstract
Moderate and high microfluidization pressures (60 and 120 MPa) and different treatment times (once and twice) were used to investigate the effect of high-pressure microfluidization (HPM) treatment on the crystallization behavior and physical properties of binary mixtures of palm stearin (PS) and [...] Read more.
Moderate and high microfluidization pressures (60 and 120 MPa) and different treatment times (once and twice) were used to investigate the effect of high-pressure microfluidization (HPM) treatment on the crystallization behavior and physical properties of binary mixtures of palm stearin (PS) and palm olein (PO). The polarized light microscopy (PLM), texture analyzer, X-ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques were applied to analyze the changes in crystal network structure, hardness, polymorphism and thermal property of the control and treated blends. PLM results showed that HPM caused significant reductions in maximum crystal diameter in all treated blends, and thus led to changes in the crystal network structure, and finally caused higher hardness in than the control blends. The XRD study demonstrated that HPM altered crystalline polymorphism. The HPM-treated blends showed a predominance of the more stable β' form, which is of more interest for food applications, while the control blend had more α- and β-form. This result was further confirmed by DSC observations. These changes in crystallization behavior indicated that HPM treatment was more likely to modify the crystallization processes and nucleation mechanisms. Full article
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Open AccessArticle Antioxidant and Antiproliferative Activities of Methanolic Extract from a Neglected Agricultural Product: Corn Cobs
Molecules 2014, 19(4), 5360-5378; doi:10.3390/molecules19045360
Received: 15 November 2013 / Revised: 4 April 2014 / Accepted: 16 April 2014 / Published: 24 April 2014
Cited by 4 | PDF Full-text (673 KB) | HTML Full-text | XML Full-text
Abstract
Neglected agricultural products (NAPs) are defined as discarded material in agricultural production. Corn cobs are a major waste of agriculture maize. Here, a methanolic extract from corn cobs (MEC) was obtained. MEC contains phenolic compounds, protein, carbohydrates (1.4:0.001:0.001). We evaluated the in [...] Read more.
Neglected agricultural products (NAPs) are defined as discarded material in agricultural production. Corn cobs are a major waste of agriculture maize. Here, a methanolic extract from corn cobs (MEC) was obtained. MEC contains phenolic compounds, protein, carbohydrates (1.4:0.001:0.001). We evaluated the in vitro and in vivo antioxidant potential of MEC. Furthermore, its antiproliferative property against tumor cells was assessed through MTT assays and proteins related to apoptosis in tumor cells were examined by western blot. MEC showed no hydroxyl radical scavenger capacity, but it showed antioxidant activity in Total Antioxidant Capacity and DPPH scavenger ability assays. MEC showed higher Reducing Power than ascorbic acid and exhibited high Superoxide Scavenging activity. In tumor cell culture, MEC increased catalase, metallothionein and superoxide dismutase expression in accordance with the antioxidant tests. In vivo antioxidant test, MEC restored SOD and CAT, decreased malondialdehyde activities and showed high Trolox Equivalent Antioxidant Capacity in animals treated with CCl4. Furthermore, MEC decreased HeLa cells viability by apoptosis due an increase of Bax/Bcl-2 ratio, caspase 3 active. Protein kinase C expression increased was also detected in treated tumor cells. Thus, our findings pointed out the biotechnological potential of corn cobs as a source of molecules with pharmacological activity. Full article
Open AccessArticle In Vitro Studies of the Activity of Dithiocarbamate Organoruthenium Complexes against Clinically Relevant Fungal Pathogens
Molecules 2014, 19(4), 5402-5420; doi:10.3390/molecules19045402
Received: 26 February 2014 / Revised: 17 April 2014 / Accepted: 22 April 2014 / Published: 24 April 2014
Cited by 2 | PDF Full-text (408 KB) | HTML Full-text | XML Full-text
Abstract
The in vitro antifungal activity of nine dirutheniumpentadithiocarbamate complexes C1C9 was investigated and assessed for its activity against four different fungal species with clinical interest and related to invasive fungal infections (IFIs), such as Candida spp. [C. albicans (two [...] Read more.
The in vitro antifungal activity of nine dirutheniumpentadithiocarbamate complexes C1C9 was investigated and assessed for its activity against four different fungal species with clinical interest and related to invasive fungal infections (IFIs), such as Candida spp. [C. albicans (two clinical isolates), C. glabrata, C. krusei, C. parapsolisis, C. tropicalis, C.dubliniensis (six clinical isolates)], Paracoccidioides brasiliensis (seven clinical isolates), Cryptococcus neoformans and Sporothrix schenckii. All synthesized complexes C1C9 and also the free ligands L1L9 were submitted to in vitro tests against those fungi and the results are very promising, since some of the obtained MIC (minimal inhibitory concentration) values were very low (from 10−6 mol mL−1 to 10−8 mol mL−1) against all investigated clinically relevant fungal pathogens, except for C. glabrata, that the MIC values are close to the ones obtained for fluconazole, the standard antifungal agent tested. Preliminary structure-activity relations (SAR) might be suggested and a strong influence from steric and lipophilic parameters in the antifungal activity can be noticed. Cytotoxicity assays (IC50) showed that the complexes are not as toxic (IC50 values are much higher—30 to 200 fold—than MIC values). These ruthenium complexes are very promising lead compounds for novel antifungal drug development, especially in IFIs, one of most harmful emerging infection diseases (EIDs). Full article
(This article belongs to the Special Issue Ruthenium Complex)
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Open AccessArticle Conformational Characterization of Ipomotaosides and Their Recognition by COX-1 and 2
Molecules 2014, 19(4), 5421-5433; doi:10.3390/molecules19045421
Received: 5 March 2014 / Revised: 18 April 2014 / Accepted: 21 April 2014 / Published: 24 April 2014
Cited by 1 | PDF Full-text (1346 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The aerial parts of Ipomoea batatas are described herein to produce four new resin glycosides, designated as ipomotaosides A, B, C, and D. Ipomotaoside A was found to present inhibitory activity on both cyclooxygenases. However, the conformational elucidation of these molecules may [...] Read more.
The aerial parts of Ipomoea batatas are described herein to produce four new resin glycosides, designated as ipomotaosides A, B, C, and D. Ipomotaoside A was found to present inhibitory activity on both cyclooxygenases. However, the conformational elucidation of these molecules may be difficult due to their high flexibility. In this context, the current work presents a conformational characterization of ipomotaosides A–D in aqueous and nonaqueous solvents. The employed protocol includes metadynamics evaluation and unrestrained molecular dynamics simulations (MD). The obtained data provided structural models for the ipomotaosides in good agreement with previous ROESY distances measured in pyridine. Accordingly, the most abundant conformation of ipomotaoside A in solution was employed in flexible docking studies, providing a structural basis for the compound’s inhibition of COX enzymes. The so-obtained complex supports resin glycosides’ role as original scaffolds for future studies, aiming at structural optimization and development of potential new anti-inflammatory agents. Full article
(This article belongs to the Special Issue Oligosaccharides and Glyco-Conjugates)
Open AccessArticle Quantification, Antioxidant and Antimicrobial Activity of Phenolics Isolated from Different Extracts of Capsicum frutescens (Pimenta Malagueta)
Molecules 2014, 19(4), 5434-5447; doi:10.3390/molecules19045434
Received: 6 January 2014 / Revised: 8 April 2014 / Accepted: 18 April 2014 / Published: 24 April 2014
Cited by 9 | PDF Full-text (287 KB) | HTML Full-text | XML Full-text
Abstract
This paper presents the quantification, antioxidant and antimicrobial activity of capsaicin, dihydrocapsaicin and the flavonoid chrysoeriol isolated from different extracts (hexane and acetonitrile extracts from whole fruit, peel and seed) of Capsicum frutescens (pimenta malagueta). The acetonitrile extract of the seeds, peel [...] Read more.
This paper presents the quantification, antioxidant and antimicrobial activity of capsaicin, dihydrocapsaicin and the flavonoid chrysoeriol isolated from different extracts (hexane and acetonitrile extracts from whole fruit, peel and seed) of Capsicum frutescens (pimenta malagueta). The acetonitrile extract of the seeds, peel and whole fruits contained capsaicin as a major component, followed in abundance by dihydrocapsaicin and chrysoeriol. The antimicrobial activity of the isolated compounds against seven microorganisms showed chrysoeriol was the most active compound. In the antioxidant test, the acetonitrile extract from the whole fruit showed the highest activity. The antioxidant activity of pimenta malagueta may be correlated with its phenolic content, principally with the most active compound, capsaicin. Full article
(This article belongs to the Section Natural Products)
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Open AccessArticle Two Ellagic Acids Isolated from Roots of Sanguisorba officinalis L. Promote Hematopoietic Progenitor Cell Proliferation and Megakaryocyte Differentiation
Molecules 2014, 19(4), 5448-5458; doi:10.3390/molecules19045448
Received: 7 March 2014 / Revised: 18 April 2014 / Accepted: 22 April 2014 / Published: 24 April 2014
Cited by 5 | PDF Full-text (322 KB) | HTML Full-text | XML Full-text
Abstract
Using a bioassay-directed chromatographic separation, two ellagic acids were obtained from the ethyl acetate extract of the roots of Sanguisorba officinalis L. On the basis of chemical and spectroscopic methods, the two ellagic acids were identified as 3,3',4-tri-O-methylellagic acid-4'-O-β [...] Read more.
Using a bioassay-directed chromatographic separation, two ellagic acids were obtained from the ethyl acetate extract of the roots of Sanguisorba officinalis L. On the basis of chemical and spectroscopic methods, the two ellagic acids were identified as 3,3',4-tri-O-methylellagic acid-4'-O-β-d-xyloside and 3,3',4-tri-O-methylellagic acid. Stimulation of cell proliferation was assayed in hematopoietic progenitor cells using the Cell Counting kit-8 method. The megakaryocyte differentiation was determined in human erythroleukemia (HEL) cells using Giemsa staining and flow cytometry analysis. The ellagic acids significantly stimulated the proliferation of Baf3/Mpl cells. Morphology analysis and megakaryocyte specific-marker CD41 staining confirmed that the ellagic acids induced megakaryocyte differentiation in HEL cells. This is the first time that 3,3',4-tri-O-methylellagic acid or 3,3',4-tri-O-methylellagic acid-4'-O-β-d-xyloside are reported to induce megakaryopoiesis, suggesting a class of small molecules which differ from others non-peptidyl, and appears to have potential for clinical development as a therapeutic agent for patients with blood platelet disorders. Full article
(This article belongs to the Section Natural Products)

Review

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Open AccessReview Superhydrophobic Surfaces Developed by Mimicking Hierarchical Surface Morphology of Lotus Leaf
Molecules 2014, 19(4), 4256-4283; doi:10.3390/molecules19044256
Received: 28 December 2013 / Revised: 26 February 2014 / Accepted: 17 March 2014 / Published: 4 April 2014
Cited by 28 | PDF Full-text (3158 KB) | HTML Full-text | XML Full-text
Abstract
The lotus plant is recognized as a ‘King plant’ among all the natural water repellent plants due to its excellent non-wettability. The superhydrophobic surfaces exhibiting the famous ‘Lotus Effect’, along with extremely high water contact angle (>150°) and [...] Read more.
The lotus plant is recognized as a ‘King plant’ among all the natural water repellent plants due to its excellent non-wettability. The superhydrophobic surfaces exhibiting the famous ‘Lotus Effect’, along with extremely high water contact angle (>150°) and low sliding angle (<10°), have been broadly investigated and extensively applied on variety of substrates for potential self-cleaning and anti-corrosive applications. Since 1997, especially after the exploration of the surface micro/nanostructure and chemical composition of the lotus leaves by the two German botanists Barthlott and Neinhuis, many kinds of superhydrophobic surfaces mimicking the lotus leaf-like structure have been widely reported in the literature. This review article briefly describes the different wetting properties of the natural superhydrophobic lotus leaves and also provides a comprehensive state-of-the-art discussion on the extensive research carried out in the field of artificial superhydrophobic surfaces which are developed by mimicking the lotus leaf-like dual scale micro/nanostructure. This review article could be beneficial for both novice researchers in this area as well as the scientists who are currently working on non-wettable, superhydrophobic surfaces. Full article
(This article belongs to the Special Issue Surface Chemistry)
Open AccessReview Magnetically Recoverable Ruthenium Catalysts in Organic Synthesis
Molecules 2014, 19(4), 4635-4653; doi:10.3390/molecules19044635
Received: 24 February 2014 / Revised: 1 April 2014 / Accepted: 10 April 2014 / Published: 15 April 2014
Cited by 13 | PDF Full-text (488 KB) | HTML Full-text | XML Full-text
Abstract
Magnetically recyclable catalysts with magnetic nanoparticles (MNPs) are becoming a major trend towards sustainable catalysts. In this area, recyclable supported ruthenium complexes and ruthenium nanoparticles occupy a key place and present great advantages compared to classic catalysts. In this micro-review, attention is [...] Read more.
Magnetically recyclable catalysts with magnetic nanoparticles (MNPs) are becoming a major trend towards sustainable catalysts. In this area, recyclable supported ruthenium complexes and ruthenium nanoparticles occupy a key place and present great advantages compared to classic catalysts. In this micro-review, attention is focused on the fabrication of MNP-supported ruthenium catalysts and their catalytic applications in various organic syntheses. Full article
(This article belongs to the Special Issue Ruthenium Complex)
Open AccessReview Sensory TRP Channel Interactions with Endogenous Lipids and Their Biological Outcomes
Molecules 2014, 19(4), 4708-4744; doi:10.3390/molecules19044708
Received: 26 February 2014 / Revised: 8 April 2014 / Accepted: 8 April 2014 / Published: 15 April 2014
Cited by 6 | PDF Full-text (1421 KB) | HTML Full-text | XML Full-text
Abstract
Lipids have long been studied as constituents of the cellular architecture and energy stores in the body. Evidence is now rapidly growing that particular lipid species are also important for molecular and cellular signaling. Here we review the current information on interactions [...] Read more.
Lipids have long been studied as constituents of the cellular architecture and energy stores in the body. Evidence is now rapidly growing that particular lipid species are also important for molecular and cellular signaling. Here we review the current information on interactions between lipids and transient receptor potential (TRP) ion channels in nociceptive sensory afferents that mediate pain signaling. Sensory neuronal TRP channels play a crucial role in the detection of a variety of external and internal changes, particularly with damaging or pain-eliciting potentials that include noxiously high or low temperatures, stretching, and harmful substances. In addition, recent findings suggest that TRPs also contribute to altering synaptic plasticity that deteriorates chronic pain states. In both of these processes, specific lipids are often generated and have been found to strongly modulate TRP activities, resulting primarily in pain exacerbation. This review summarizes three standpoints viewing those lipid functions for TRP modulations as second messengers, intercellular transmitters, or bilayer building blocks. Based on these hypotheses, we discuss perspectives that account for how the TRP-lipid interaction contributes to the peripheral pain mechanism. Still a number of blurred aspects remain to be examined, which will be answered by future efforts and may help to better control pain states. Full article
(This article belongs to the Special Issue Fatty Acids)
Open AccessReview Granulocyte Colony-Stimulating Factor in the Treatment of Acute Radiation Syndrome: A Concise Review
Molecules 2014, 19(4), 4770-4778; doi:10.3390/molecules19044770
Received: 28 January 2014 / Revised: 17 March 2014 / Accepted: 11 April 2014 / Published: 16 April 2014
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Abstract
This article concisely summarizes data on the action of one of the principal and best known growth factors, the granulocyte colony-stimulating factor (G-CSF), in a mammalian organism exposed to radiation doses inducing acute radiation syndrome. Highlighted are the topics of its real [...] Read more.
This article concisely summarizes data on the action of one of the principal and best known growth factors, the granulocyte colony-stimulating factor (G-CSF), in a mammalian organism exposed to radiation doses inducing acute radiation syndrome. Highlighted are the topics of its real or anticipated use in radiation accident victims, the timing of its administration, the possibilities of combining G-CSF with other drugs, the ability of other agents to stimulate endogenous G-CSF production, as well as of the capability of this growth factor to ameliorate not only the bone marrow radiation syndrome but also the gastrointestinal radiation syndrome. G-CSF is one of the pivotal drugs in the treatment of radiation accident victims and its employment in this indication can be expected to remain or even grow in the future. Full article
Open AccessReview RutheniumII Complexes bearing Fused Polycyclic Ligands: From Fundamental Aspects to Potential Applications
Molecules 2014, 19(4), 5028-5087; doi:10.3390/molecules19045028
Received: 28 February 2014 / Revised: 15 April 2014 / Accepted: 16 April 2014 / Published: 22 April 2014
Cited by 6 | PDF Full-text (1408 KB) | HTML Full-text | XML Full-text
Abstract
In this review, we first discuss the photophysics reported in the literature for mononuclear ruthenium complexes bearing ligands with extended aromaticity such as dipyrido[3,2-a:2',3'-c]phenazine (DPPZ), tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]-phenazine (TPPHZ),  tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]acridine (TPAC), 1,10-phenanthrolino[5,6-b]1,4,5,8,9,12-hexaazatriphenylene (PHEHAT) 9,11,20,22-tetraaza- tetrapyrido[3,2-a:2',3'-c:3'',2''-l:2''',3'''-n]pentacene (TATPP), etc. Photophysical properties of binuclear and polynuclear complexes [...] Read more.
In this review, we first discuss the photophysics reported in the literature for mononuclear ruthenium complexes bearing ligands with extended aromaticity such as dipyrido[3,2-a:2',3'-c]phenazine (DPPZ), tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]-phenazine (TPPHZ),  tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]acridine (TPAC), 1,10-phenanthrolino[5,6-b]1,4,5,8,9,12-hexaazatriphenylene (PHEHAT) 9,11,20,22-tetraaza- tetrapyrido[3,2-a:2',3'-c:3'',2''-l:2''',3'''-n]pentacene (TATPP), etc. Photophysical properties of binuclear and polynuclear complexes based on these extended ligands are then reported. We finally develop the use of binuclear complexes with extended π-systems for applications such as photocatalysis. Full article
(This article belongs to the Special Issue Ruthenium Complex)
Open AccessReview Natural Dibenzo-α-Pyrones and Their Bioactivities
Molecules 2014, 19(4), 5088-5108; doi:10.3390/molecules19045088
Received: 19 February 2014 / Revised: 16 April 2014 / Accepted: 16 April 2014 / Published: 22 April 2014
Cited by 10 | PDF Full-text (279 KB) | HTML Full-text | XML Full-text
Abstract
Natural dibenzo-α-pyrones are an important group of metabolites derived from fungi, mycobionts, plants and animal feces. They exhibit a variety of biological activities such as toxicity on human and animals, phytotoxicity as well as cytotoxic, antioxidant, antiallergic, antimicrobial, antinematodal, and acetylcholinesterase inhibitory [...] Read more.
Natural dibenzo-α-pyrones are an important group of metabolites derived from fungi, mycobionts, plants and animal feces. They exhibit a variety of biological activities such as toxicity on human and animals, phytotoxicity as well as cytotoxic, antioxidant, antiallergic, antimicrobial, antinematodal, and acetylcholinesterase inhibitory properties. Dibenzo-α-pyrones are biosynthesized via the polyketide pathway in microorganisms or metabolized from plant-derived ellagitannins and ellagic acid by intestinal bacteria. At least 53 dibenzo-α-pyrones have been reported in the past few decades. This mini-review aims to briefly summarize the occurrence, biosynthesis, biotransformation, as well as their biological activities and functions. Some considerations related to synthesis, production and applications of dibenzo-α-pyrones are also discussed. Full article
(This article belongs to the Section Natural Products)
Open AccessReview Role of MicroRNA in Response to Ionizing Radiations: Evidences and Potential Impact on Clinical Practice for Radiotherapy
Molecules 2014, 19(4), 5379-5401; doi:10.3390/molecules19045379
Received: 10 February 2014 / Revised: 17 April 2014 / Accepted: 23 April 2014 / Published: 24 April 2014
Cited by 19 | PDF Full-text (293 KB) | HTML Full-text | XML Full-text
Abstract
MicroRNAs (miRNA) are small, non-coding, RNAs with gene expression regulator roles. As an important class of regulators of many cellular pathways, miRNAs are involved in many signaling pathways and DNA damage repair processes, affecting cellular radiosensitivity. Their role has led to interest [...] Read more.
MicroRNAs (miRNA) are small, non-coding, RNAs with gene expression regulator roles. As an important class of regulators of many cellular pathways, miRNAs are involved in many signaling pathways and DNA damage repair processes, affecting cellular radiosensitivity. Their role has led to interest in oncological implications to improve treatment results. MiRNAs represent a great opportunity to enhance the efficacy of radiotherapy treatments—they can be used to profile the radioresistance of tumors before radiotherapy, monitor their response throughout the treatment, thus helping to select intensification strategies, and also to define the final response to therapy along with risks of recurrence or metastatization. Even though many interesting studies support such potential, nowadays most studies on patient data are limited to experiments profiling tumor aggressiveness and response to radiotherapy. Moreover many studies report different although not conflicting results on the miRNAs evaluated for each tumor type. Without doubt, the clinical potential of such molecules for radiotherapy is striking and of high interest. Full article
(This article belongs to the Special Issue miRNAs as Probes to Monitor Cancer and Neurodegenerative Disorders)

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