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Molecules, Volume 18, Issue 4 (April 2013), Pages 3641-4843

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Open AccessArticle Theoretical Analysis on the Kinetic Isotope Effects of Bimolecular Nucleophilic Substitution (SN2) Reactions and Their Temperature Dependence
Molecules 2013, 18(4), 4816-4843; https://doi.org/10.3390/molecules18044816
Received: 13 March 2013 / Revised: 3 April 2013 / Accepted: 18 April 2013 / Published: 23 April 2013
Cited by 7 | PDF Full-text (458 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Factors affecting the kinetic isotope effects (KIEs) of the gas-phase SN2 reactions and their temperature dependence have been analyzed using the ion-molecule collision theory and the transition state theory (TST). The quantum-mechanical tunneling effects were also considered using the canonical variational
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Factors affecting the kinetic isotope effects (KIEs) of the gas-phase SN2 reactions and their temperature dependence have been analyzed using the ion-molecule collision theory and the transition state theory (TST). The quantum-mechanical tunneling effects were also considered using the canonical variational theory with small curvature tunneling (CVT/SCT). We have benchmarked a few ab initio and density functional theory (DFT) methods for their performance in predicting the deuterium KIEs against eleven experimental values. The results showed that the MP2/aug-cc-pVDZ method gave the most accurate prediction overall. The slight inverse deuterium KIEs usually observed for the gas-phase SN2 reactions at room temperature were due to the balance of the normal rotational contribution and the significant inverse vibrational contribution. Since the vibrational contribution is a sensitive function of temperature while the rotation contribution is temperature independent, the KIEs are thus also temperature dependent. For SN2 reactions with appreciable barrier heights, the tunneling effects were predicted to contribute significantly both to the rate constants and to the carbon-13, and carbon-14 KIEs, which suggested important carbon atom tunneling at and below room temperature. Full article
(This article belongs to the Special Issue Isotope Effects)
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Open AccessArticle Intravenous and Subcutaneous Toxicity and Absorption Kinetics in Mice and Dogs of the Antileishmanial Triterpene Saponin PX-6518
Molecules 2013, 18(4), 4803-4815; https://doi.org/10.3390/molecules18044803
Received: 16 February 2013 / Revised: 7 April 2013 / Accepted: 19 April 2013 / Published: 22 April 2013
Cited by 2 | PDF Full-text (939 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The intravenous (IV) and subcutaneous (SC) toxicity and absorption kinetics of the antileishmanial triterpene saponin PX-6518 and its active constituents maesabalide-III and -IV were studied in mice and dogs. A high-dose wash-out study of PX-6518 at 20 mg/kg SC for 5 days and
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The intravenous (IV) and subcutaneous (SC) toxicity and absorption kinetics of the antileishmanial triterpene saponin PX-6518 and its active constituents maesabalide-III and -IV were studied in mice and dogs. A high-dose wash-out study of PX-6518 at 20 mg/kg SC for 5 days and a single low-dose wash-out study at 1, 2.5 or 5 mg/kg SC and IV with follow-up until day 35 after treatment were performed in mice. Beagle dogs received three escalating doses of maesabalide-III and -IV at weekly intervals (0.01, 0.1 and 0.5 mg/kg IV and maesabalide-III was also dosed SC at 0.1, 0.2 and 0.4 mg/kg). Endpoint measurements included clinical, hematological and serum biochemical parameters. Pathology and toxicokinetic studies were performed on the dogs. Whereas the neutrophils and aspartate aminotransferase and alanine aminotransferase levels were increased in the high-dose wash-out mouse study, these parameters did not change in the low-dose wash-out study. The dogs were far more susceptible than mice to liver toxicity (hepatocellular necrosis and elevated liver enzymes) and developed a painful inflammatory reaction at the SC injection site. Toxicokinetic analysis revealed a non dose-linear systemic availability with plasma concentrations above the antileishmanial IC50 after only a single dose at 0.01 mg/kg IV or 0.1 mg/kg SC. Related to the long half-life (T1/2 71–91 h after SC dosing), repeated dosing at weekly intervals may result in drug accumulation and enhanced toxicity. It was decided not to pursue further drug development for PX-6518 because of the hepatotoxic risk. Full article
(This article belongs to the Special Issue Triterpenes and Triterpenoids 2013)
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Open AccessArticle 1H-MAS-NMR Chemical Shifts in Hydrogen-Bonded Complexes of Chlorophenols (Pentachlorophenol, 2,4,6-Trichlorophenol, 2,6-Dichlorophenol, 3,5-Dichlorophenol, and p-Chlorophenol) and Amine, and H/D Isotope Effects on 1H-MAS-NMR Spectra
Molecules 2013, 18(4), 4786-4802; https://doi.org/10.3390/molecules18044786
Received: 1 March 2013 / Revised: 12 April 2013 / Accepted: 18 April 2013 / Published: 22 April 2013
Cited by 4 | PDF Full-text (564 KB) | HTML Full-text | XML Full-text
Abstract
Chemical shifts (CS) of the 1H nucleus in N···H···O type hydrogen bonds (H-bond) were observed in some complexes between chlorophenols [pentachlorophenol (PCP), 2,4,6-tricholorophenol (TCP), 2,6-dichlorophenol (26DCP), 3,5-dichlorophenol (35DCP), and p-chlorophenol (pCP)] and nitrogen-base (N-Base) by solid-state high-resolution 1H-NMR
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Chemical shifts (CS) of the 1H nucleus in N···H···O type hydrogen bonds (H-bond) were observed in some complexes between chlorophenols [pentachlorophenol (PCP), 2,4,6-tricholorophenol (TCP), 2,6-dichlorophenol (26DCP), 3,5-dichlorophenol (35DCP), and p-chlorophenol (pCP)] and nitrogen-base (N-Base) by solid-state high-resolution 1H-NMR with the magic-angle-spinning (MAS) method. Employing N-Bases with a wide range of pKa values (0.65–10.75), 1H-MAS-NMR CS values of bridging H atoms in H-bonds were obtained as a function of the N-Base’s pKa. The result showed that the CS values were increased with increasing pKa values in a range of DpKa < 0 [DpKa = pKa(N-Base) - pKa(chlorophenols)] and decreased when DpKa > 2: The maximum CS values was recorded in the PCP (pKa = 5.26)–4-methylpyridine (6.03), TCP (6.59)–imidazole (6.99), 26DCP (7.02)–2-amino-4-methylpyridine (7.38), 35DCP (8.04)–4-dimethylaminopyridine (9.61), and pCP (9.47)–4-dimethylaminopyridine (9.61) complexes. The largest CS value of 18.6 ppm was recorded in TCP–imidazole crystals. In addition, H/D isotope effects on 1H-MAS-NMR spectra were observed in PCP–2-amino-3-methylpyridine. Based on the results of CS simulation using a B3LYP/6-311+G** function, it can be explained that a little changes of the N–H length in H-bond contribute to the H/D isotope shift of the 1H-MAS-NMR peaks. Full article
(This article belongs to the Special Issue Isotope Effects)
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Open AccessArticle Computational Modeling of the Size Effects on the Optical Vibrational Modes of H-Terminated Ge Nanostructures
Molecules 2013, 18(4), 4776-4785; https://doi.org/10.3390/molecules18044776
Received: 16 January 2013 / Revised: 16 April 2013 / Accepted: 18 April 2013 / Published: 22 April 2013
Cited by 5 | PDF Full-text (974 KB) | HTML Full-text | XML Full-text
Abstract
The vibrational dispersion relations of porous germanium (pGe) and germanium nanowires (GeNWs) were calculated using the ab initio density functional perturbation theory with a generalized gradient approximation with norm-conserving pseudopotentials. Both pores and nanowires were modeled using the supercell technique. All of the
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The vibrational dispersion relations of porous germanium (pGe) and germanium nanowires (GeNWs) were calculated using the ab initio density functional perturbation theory with a generalized gradient approximation with norm-conserving pseudopotentials. Both pores and nanowires were modeled using the supercell technique. All of the surface dangling bonds were saturated with hydrogen atoms. To address the difference in the confinement between the pores and the nanowires, we calculated the vibrational density of states of the two materials. The results indicate that there is a slight shift in the highest optical mode of the Ge-Ge vibration interval in all of the nanostructures due to the phonon confinement effects. The GeNWs exhibit a reduced phonon confinement compared with the porous Ge due to the mixed Ge-dihydride vibrational modes around the maximum bulk Ge optical mode of approximately 300 cm−1; however, the general effects of such confinements could still be noticed, such as the shift to lower frequencies of the highest optical mode belonging to the Ge vibrations. Full article
(This article belongs to the Special Issue Computational Chemistry)
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Open AccessArticle Chemical Constituents of the Root of Jasminum giraldii
Molecules 2013, 18(4), 4766-4775; https://doi.org/10.3390/molecules18044766
Received: 1 February 2013 / Revised: 26 March 2013 / Accepted: 12 April 2013 / Published: 22 April 2013
Cited by 12 | PDF Full-text (264 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Two new compounds, ethylconiferin (1) and (−)-lariciresinol 4-(6'''-O-cinnamyl-β-d-glucopyranoside) (2), along with the three known compounds (+)-pinoresinol (3), (+)-cycloolivil (4), nobiletin (5), were isolated from the root of Jasminum girialdii
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Two new compounds, ethylconiferin (1) and (−)-lariciresinol 4-(6'''-O-cinnamyl-β-d-glucopyranoside) (2), along with the three known compounds (+)-pinoresinol (3), (+)-cycloolivil (4), nobiletin (5), were isolated from the root of Jasminum girialdii. All these compounds were isolated for the first time from this source. Their structures were elucidated on the basis of extensive spectroscopic analysis and chemical methods. In addition, the in vitro cytotoxic activity of these compounds was evaluated. The results showed that none of the compounds had any significant inhibitory activities on the proliferation of HCT-116 and SW-620 cells. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessReview Application of the Suzuki-Miyaura Reaction in the Synthesis of Flavonoids
Molecules 2013, 18(4), 4739-4765; https://doi.org/10.3390/molecules18044739
Received: 19 March 2013 / Revised: 10 April 2013 / Accepted: 19 April 2013 / Published: 22 April 2013
Cited by 25 | PDF Full-text (350 KB) | HTML Full-text | XML Full-text
Abstract
The application of the Suzuki-Miyaura reaction in the synthesis of flavonoids, an important class of natural products, is reviewed. This reaction has not only been employed to provide access to flavonoid nuclei, but has also been applied to the synthesis of dimeric flavonoids
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The application of the Suzuki-Miyaura reaction in the synthesis of flavonoids, an important class of natural products, is reviewed. This reaction has not only been employed to provide access to flavonoid nuclei, but has also been applied to the synthesis of dimeric flavonoids and in the synthesis of libraries of flavonoid derivatives for biological activity studies. The classes of flavonoids that are discussed are the chalcones, flavones, isoflavones, neoflavones, biflavones and derivatives of flavonoids obtained by C-C bond formation via the Suzuki-Miyaura reaction. Full article
(This article belongs to the Special Issue Suzuki Reaction)
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Open AccessArticle A New Vanadium (III) Complex of 2,6-Bis(3,5-diphenylpyrazol-1-ylmethyl)pyridine as a Catalyst for Ethylene Polymerization
Molecules 2013, 18(4), 4728-4738; https://doi.org/10.3390/molecules18044728
Received: 11 March 2013 / Revised: 17 April 2013 / Accepted: 18 April 2013 / Published: 22 April 2013
Cited by 14 | PDF Full-text (326 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The tridentate ligand 2,6-bis(3,5-diphenylpyrazol-1-ylmethyl)pyridine, abbreviated as 2,6-[(3,5-ph2pz-CH2)2-py], a new pyridine-pyrazole derivative, was prepared from 2,6-bis(bromomethyl)pyridine and 3,5-diphenylpyrazole. The ligand was characterized by means of elemental analyses, ATR-IR, 1H- and 13C-NMR spectroscopy and single crystal X-ray
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The tridentate ligand 2,6-bis(3,5-diphenylpyrazol-1-ylmethyl)pyridine, abbreviated as 2,6-[(3,5-ph2pz-CH2)2-py], a new pyridine-pyrazole derivative, was prepared from 2,6-bis(bromomethyl)pyridine and 3,5-diphenylpyrazole. The ligand was characterized by means of elemental analyses, ATR-IR, 1H- and 13C-NMR spectroscopy and single crystal X-ray crystallography. Using this ligand, a new mononuclear vanadium (III) complex, {2,6-[(3,5-ph2pz)CH2]2py}VCl3 was prepared and characterized by elemental analysis, ATR-IR and HR-MS. The complex was investigated as a catalyst for ethylene polymerization and compared with 2,6-[(3,5-Me2pz)CH2]2py}VCl3 to explore the effect of the substituent on the pyrazolyl rings on ethylene polymerization. High catalytic activity was observed at ambient temperature. After treatment with AlEtCl2, these complexes showed high activity for ethylene polymerization converting ethylene to highly linear polyethylene and affording high molecular weight polymers (up to 1.0 × 106 g/mol) with unimodal molecular weight distributions. Full article
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Open AccessArticle New Amide Derivatives of Quinoxaline 1,4-di-N-Oxide with Leishmanicidal and Antiplasmodial Activities
Molecules 2013, 18(4), 4718-4727; https://doi.org/10.3390/molecules18044718
Received: 26 March 2013 / Revised: 11 April 2013 / Accepted: 18 April 2013 / Published: 22 April 2013
Cited by 19 | PDF Full-text (192 KB) | HTML Full-text | XML Full-text
Abstract
Malaria and leishmaniasis are two of the World’s most important tropical parasitic diseases. Continuing with our efforts to identify new compounds active against malaria and leishmaniasis, twelve new 1,4-di-N-oxide quinoxaline derivatives were synthesized and evaluated for their in vitro antimalarial and
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Malaria and leishmaniasis are two of the World’s most important tropical parasitic diseases. Continuing with our efforts to identify new compounds active against malaria and leishmaniasis, twelve new 1,4-di-N-oxide quinoxaline derivatives were synthesized and evaluated for their in vitro antimalarial and antileishmanial activity against Plasmodium falciparum FCR-3 strain, Leishmania infantum and Leishmania amazonensis. Their toxicity against VERO cells (normal monkey kidney cells) was also assessed. The results obtained indicate that a cyclopentyl derivative had the best antiplasmodial activity (2.9 µM), while a cyclohexyl derivative (2.5 µM) showed the best activity against L. amazonensis, and a 3-chloropropyl derivative (0.7 µM) showed the best results against L. infantum. All these compounds also have a Cl substituent in the R7 position. Full article
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Open AccessReview Applications of Biomaterials to Liquid Crystals
Molecules 2013, 18(4), 4703-4717; https://doi.org/10.3390/molecules18044703
Received: 17 January 2013 / Revised: 10 April 2013 / Accepted: 17 April 2013 / Published: 19 April 2013
Cited by 19 | PDF Full-text (369 KB) | HTML Full-text | XML Full-text
Abstract
Nowadays, chemically synthesized proteins and peptides are attractive building blocks and have potential in many important applications as biomaterials. In this review, applications of biomaterials to thermotropic liquid crystals are discussed. The review covers the improvement of the performance of liquid crystal displays
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Nowadays, chemically synthesized proteins and peptides are attractive building blocks and have potential in many important applications as biomaterials. In this review, applications of biomaterials to thermotropic liquid crystals are discussed. The review covers the improvement of the performance of liquid crystal displays using liquid crystal physical gels consisting of a liquid crystal and amino acid-based gelators, and also new functionalization of liquid crystals. Moreover, the influence of DNA, which is one of the more attractive biomaterials, dispersed in thermotropic liquid crystals and its potential use in the liquid crystal industry is described. In addition, we found interesting results during electrooptical measurements of liquid crystals doped with DNA, and explain them from the point of view of biological applications. These recent approaches suggest that these biomaterials may be applicable in the electronic device industry and should be considered as an interesting material with their physical properties having the potential to create or refine an industrial product. Full article
(This article belongs to the Special Issue Chemical Protein and Peptide Synthesis)
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Open AccessArticle Resveratrol Protects against Physical Fatigue and Improves Exercise Performance in Mice
Molecules 2013, 18(4), 4689-4702; https://doi.org/10.3390/molecules18044689
Received: 4 February 2013 / Revised: 17 April 2013 / Accepted: 18 April 2013 / Published: 19 April 2013
Cited by 48 | PDF Full-text (2944 KB) | HTML Full-text | XML Full-text
Abstract
Resveratrol (RES) is a well-known phytocompound and food component which has antioxidative and multifunctional bioactivities. However, there is limited evidence for the effects of RES on physical fatigue and exercise performance. The purpose of this study was to evaluate the potential beneficial effects
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Resveratrol (RES) is a well-known phytocompound and food component which has antioxidative and multifunctional bioactivities. However, there is limited evidence for the effects of RES on physical fatigue and exercise performance. The purpose of this study was to evaluate the potential beneficial effects of trans-RES on fatigue and ergogenic functions following physiological challenge. Male ICR mice from four groups (n = 8 per group) were orally administered RES for 21 days at 0, 25, 50, and 125 mg/kg/day, which were respectively designated the vehicle, RES-25, RES-50, and RES-125 groups. The anti-fatigue activity and exercise performance were evaluated using forelimb grip strength, exhaustive swimming time, and levels of serum lactate, ammonia, glucose, and creatine kinase (CK) after a 15-min swimming exercise. The exhaustive swimming time of the RES-25 group (24.72 ± 7.35 min) was significantly (p = 0.0179) longer than that of vehicle group (10.83 ± 1.15 min). A trend analysis revealed that RES treatments increased the grip strength. RES supplementation also produced dose-dependent decreases in serum lactate and ammonia levels and CK activity and also an increase in glucose levels in dose-dependent manners after the 15-min swimming test. The mechanism was related to the increased energy utilization (as blood glucose), and decreased serum levels of lactate, ammonia, and CK. Therefore, RES could be a potential agent with an anti-fatigue pharmacological effect. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Microwave-Assisted Synthesis of New Selenazole Derivatives with Antiproliferative Activity
Molecules 2013, 18(4), 4679-4688; https://doi.org/10.3390/molecules18044679
Received: 11 March 2013 / Revised: 12 April 2013 / Accepted: 17 April 2013 / Published: 19 April 2013
Cited by 12 | PDF Full-text (212 KB) | HTML Full-text | XML Full-text
Abstract
New aryl-hydrazinyl-1,3-selenazole and aroyl-hydrazonyl-1,3-selenazoles were synthesized via Hantzsch type condensation reactions of selenosemicarbazides with α-halogenocarbonyl derivatives, under classical versus microwave heating conditions. Excellent yields and shorter reaction times were obtained under irradiation conditions. The structures of the synthesized compounds were assigned based on
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New aryl-hydrazinyl-1,3-selenazole and aroyl-hydrazonyl-1,3-selenazoles were synthesized via Hantzsch type condensation reactions of selenosemicarbazides with α-halogenocarbonyl derivatives, under classical versus microwave heating conditions. Excellent yields and shorter reaction times were obtained under irradiation conditions. The structures of the synthesized compounds were assigned based on spectroscopic data (FT-IR, 1H-NMR), MS and elemental analysis. Selenazole derivatives were screened for their anti-proliferative effects against two leukemia cell lines (CCRF-CEM and HL60) and three carcinoma cell lines (MDA-MB231, HCT116 and U87MG). Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Synthesis and Antimicrobial Activity of Some New Thieno[2,3-b]thiophene Derivatives
Molecules 2013, 18(4), 4669-4678; https://doi.org/10.3390/molecules18044669
Received: 28 March 2013 / Revised: 10 April 2013 / Accepted: 16 April 2013 / Published: 19 April 2013
Cited by 10 | PDF Full-text (305 KB) | HTML Full-text | XML Full-text
Abstract
A series of thieno[2,3-b]thiophene moiety-containing bis-cyanopyrazoles 5ac, bis-aminopyrazole 9 and bis-pyridazine derivatives 11 were synthesized and evaluated in vitro for their antimicrobial potential. The antimicrobial activity of some selected products was evaluated and showed good
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A series of thieno[2,3-b]thiophene moiety-containing bis-cyanopyrazoles 5ac, bis-aminopyrazole 9 and bis-pyridazine derivatives 11 were synthesized and evaluated in vitro for their antimicrobial potential. The antimicrobial activity of some selected products was evaluated and showed good results. 5,5'-(3,4-Dimethylthieno[2,3-b]thiophene-2,5-diyl)bis(3-acetyl-1-(4-chlorophenyl)-1H-pyrazole-4-carbonitrile) (5d) was found to be more potent than the standard drug amphotericin B against Geotricum candidum and equipotent to amphotericin B against Syncephalastrum racemosum. In addition, it was found to be equipotent to the standard drug Penicillin G against Staphylococcus aureus. Moreover, it was more potent than the standard drug streptomycin against Pseudomonas aeruginosa and Escherichia coli. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Evaluation of Biological Value and Appraisal of Polyphenols and Glucosinolates from Organic Baby-Leaf Salads as Antioxidants and Antimicrobials against Important Human Pathogenic Bacteria
Molecules 2013, 18(4), 4651-4668; https://doi.org/10.3390/molecules18044651
Received: 14 March 2013 / Revised: 12 April 2013 / Accepted: 17 April 2013 / Published: 19 April 2013
Cited by 5 | PDF Full-text (340 KB) | HTML Full-text | XML Full-text
Abstract
The present investigation has been carried out to investigate the biological role of four different types of baby-leaf salads and to study their potential as natural sources of antioxidants and antimicrobials against several isolates from important human pathogenic bacteria. Four single types of
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The present investigation has been carried out to investigate the biological role of four different types of baby-leaf salads and to study their potential as natural sources of antioxidants and antimicrobials against several isolates from important human pathogenic bacteria. Four single types of salads (green lettuce, red lettuce, rucola and watercress) and two mixtures [(1) red lettuce+green lettuce; (2) green lettuce + red lettuce + watercress + rucola] were assayed. The HPLC analysis revealed interesting levels of polyphenols and glucosinolates. The results showed a significant variation (p < 0.05) of polyphenols and glucosinolates with plant material. Nine different types of polyphenols grouped in three major classes were found: gallic acid, chlorogenic acid, caffeic acid and dicaffeoyltartaric acid (phenolic acids); quercitin-3-O-rutinoside, quercitin-3-O-rhamnoside, luteolin-7-O-glucoside and isorhamnetin (flavonoids); and cyanidin-3-glucoside (anthocyanins). Only three different glucosinolates were found: glucoraphanin; gluconasturtiin and 4-methoxy-glucobrassicin. A positive correlation was detected between polyphenol contents and antioxidant activity. Red lettuce and mixture 1 were the baby-leaf salads with the highest antioxidant potential. As for the antimicrobial activity, the results showed a selective effect of chemicals against Gram-positive and Gram-negative bacteria and Enterococcus faecalis and Staphylococcus aureus were the bacteria most affected by the phytochemicals. Based on the results achieved baby-leaf salads represent an important source of natural antioxidants and antimicrobial substances. Full article
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Open AccessCommunication Arabinoxylan Microspheres: Structural and Textural Characteristics
Molecules 2013, 18(4), 4640-4650; https://doi.org/10.3390/molecules18044640
Received: 8 February 2013 / Revised: 7 April 2013 / Accepted: 8 April 2013 / Published: 19 April 2013
Cited by 10 | PDF Full-text (586 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this research was to study the structural and textural characteristics of maize bran arabinoxylan (MBAX) microspheres. The laccase-induced cross-linking process was monitored by storage (G') and loss (G'') moduli changes in a 4% (w/v) MBAX solution. The G' and G''
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The aim of this research was to study the structural and textural characteristics of maize bran arabinoxylan (MBAX) microspheres. The laccase-induced cross-linking process was monitored by storage (G') and loss (G'') moduli changes in a 4% (w/v) MBAX solution. The G' and G'' values at the plateau region were 215 and 4 Pa, respectively. After gelation, the content of ferulic acid dimers decreased from 0.135 to 0.03 µg/mg MBAX, suggesting the formation of ferulated structures unreleased by mild alkaline hydrolysis. MBAX microspheres presented an average diameter of 531 µm and a swelling ratio value (q) of 18 g water/g MBAX. The structural parameters of MBAX microspheres were calculated from equilibrium swelling experiments, presenting an average mesh size of 52 nm. Microstructure and textural properties of dried MBAX microspheres were studied by scanning electron microscopy and nitrogen adsorption/desorption isotherms, respectively, showing a heterogeneous mesoporous and macroporous structure throughout the network. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessCommunication A Series of Asymmetrical Phthalocyanines: Synthesis and Near Infrared Properties
Molecules 2013, 18(4), 4628-4639; https://doi.org/10.3390/molecules18044628
Received: 30 January 2013 / Revised: 7 April 2013 / Accepted: 8 April 2013 / Published: 19 April 2013
Cited by 3 | PDF Full-text (390 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
We report here the preparation of asymmetrical phthalocyanine dimers 1a3a, which are endowed with novel charge transfer bands at 1,151–1,154 nm and strong NIR luminescences at 840–860 nm and 1,600–1,650 nm. Through H-bonding interaction, 1a3a are inclined to
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We report here the preparation of asymmetrical phthalocyanine dimers 1a3a, which are endowed with novel charge transfer bands at 1,151–1,154 nm and strong NIR luminescences at 840–860 nm and 1,600–1,650 nm. Through H-bonding interaction, 1a3a are inclined to self-assemble into hexrod nanotubes at the interface of CHCl3 and CH3OH. Our results provide further insights into the interaction in molecular dimers, and suggest that 1a3a have potential application in magnets and supramolecular architectures. Full article
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