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Molecules, Volume 18, Issue 2 (February 2013) – 81 articles , Pages 1337-2457

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Editorial

Jump to: Research, Review

116 KiB  
Editorial
Molecules Best Paper Award 2013
by Derek J. McPhee
Molecules 2013, 18(2), 2081-2083; https://doi.org/10.3390/molecules18022081 - 5 Feb 2013
Viewed by 5443
Abstract
Molecules has started to institute a "Best Paper" award to recognize the most outstanding papers in the area of natural products, medicinal chemistry and molecular diversity published in Molecules. We are pleased to announce the second "Molecules Best Paper Award" for [...] Read more.
Molecules has started to institute a "Best Paper" award to recognize the most outstanding papers in the area of natural products, medicinal chemistry and molecular diversity published in Molecules. We are pleased to announce the second "Molecules Best Paper Award" for 2013. Candidates were chosen by the Editor-in-Chief and selected editorial board members from among all the papers published in 2009. [...] Full article
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Research

Jump to: Editorial, Review

977 KiB  
Article
Profiling and Characterization of Volatile Components from Non-Fumigated and Sulfur-Fumigated Flos Lonicerae Japonicae Using Comprehensive Two-Dimensional Gas Chromatography Time-of-Flight Mass Spectrometry Coupled with Chemical Group Separation
by Hao Cai, Gang Cao, Li Li, Xiao Liu, Xiao-Qing Ma, Si-Cong Tu, Ya-Jing Lou, Kun-Ming Qin, Song-Lin Li and Bao-Chang Cai
Molecules 2013, 18(2), 1368-1382; https://doi.org/10.3390/molecules18021368 - 24 Jan 2013
Cited by 30 | Viewed by 12455
Abstract
Flos Lonicerae Japonicae (FLJ) is a popular herb used for many centuries in Traditional Chinese Medicine as a treatment of fever and inflammation. Non-fumigated processing of FLJ has been the traditional approach used in post-harvest preparation of the commodity for commercial use. However, [...] Read more.
Flos Lonicerae Japonicae (FLJ) is a popular herb used for many centuries in Traditional Chinese Medicine as a treatment of fever and inflammation. Non-fumigated processing of FLJ has been the traditional approach used in post-harvest preparation of the commodity for commercial use. However, in recent years, natural drying processing of FLJ has been replaced by sulfur-fumigation for efficiency and pest control. Sulfur-fumigation can induce changes in the volatile compounds of the herb, altering its medicinal properties. A comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOF/MS) method was established for the resolution and determination of volatile components in non-fumigated and sulfur-fumigated FLJ. In this paper, analysis of the volatile oils in non-fumigated and sulfur-fumigated (including lab-prepared sulfur- fumigated and industrial sulfur-fumigated) FLJ was performed using GC×GC-TOF/MS. Seventy-three representative volatile components were identified, including furans, alkalies, acids, aldehydes, ketones, alcohols, terpenes, esters, and others, as the main components of FLJ volatile oils. The proposed method was successfully applied for rapid and accurate quality evaluation of FLJ and its related medicinal materials and preparations. Full article
(This article belongs to the Section Medicinal Chemistry)
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213 KiB  
Article
Synthesis and Structure-Activity Relationships of Novel Amino/Nitro Substituted 3-Arylcoumarins as Antibacterial Agents
by Maria J. Matos, Saleta Vazquez-Rodriguez, Lourdes Santana, Eugenio Uriarte, Cristina Fuentes-Edfuf, Ysabel Santos and Angeles Muñoz-Crego
Molecules 2013, 18(2), 1394-1404; https://doi.org/10.3390/molecules18021394 - 24 Jan 2013
Cited by 63 | Viewed by 5400
Abstract
A new series of amino/nitro-substituted 3-arylcoumarins were synthesized and their antibacterial activity against clinical isolates of Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) was evaluated. Some of these molecules exhibited antibacterial activity against S. aureus comparable to the standards used (oxolinic acid and [...] Read more.
A new series of amino/nitro-substituted 3-arylcoumarins were synthesized and their antibacterial activity against clinical isolates of Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) was evaluated. Some of these molecules exhibited antibacterial activity against S. aureus comparable to the standards used (oxolinic acid and ampicillin). The preliminary structure-activity relationship (SAR) study showed that the antibacterial activity against S. aureus depends on the position of the 3-arylcoumarin substitution pattern. With the aim of finding the structural features for the antibacterial activity and selectivity, in the present manuscript different positions of nitro, methyl, methoxy, amino and bromo substituents on the 3-arylcoumarin scaffold were reported. Full article
(This article belongs to the Section Medicinal Chemistry)
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271 KiB  
Article
Cytotoxic and Radical Scavenging Nor-Dammarane Triterpenoids from Viburnum mongolicum
by Xiaohua Wang and Wei Wang
Molecules 2013, 18(2), 1405-1417; https://doi.org/10.3390/molecules18021405 - 24 Jan 2013
Cited by 7 | Viewed by 4730
Abstract
The ethanol extract of the whole plants of Viburnum mongolicum afforded six new nor-dammarane triterpenoids: 3β,12β-dihydroxy-25,26,27-trinordammara-22-en -24,20-olide (1), 3β,12β-dihydroxy-24α-methoxy-25,26,27-trinordammara-20,24-epoxy (2), 3β-O-acetyl-12β-hydroxy-23,24,25,26,27-hexanordammarane-20-one (3 [...] Read more.
The ethanol extract of the whole plants of Viburnum mongolicum afforded six new nor-dammarane triterpenoids: 3β,12β-dihydroxy-25,26,27-trinordammara-22-en -24,20-olide (1), 3β,12β-dihydroxy-24α-methoxy-25,26,27-trinordammara-20,24-epoxy (2), 3β-O-acetyl-12β-hydroxy-23,24,25,26,27-hexanordammarane-20-one (3), 12β-O- acetyl-15α-hydroxy-17β-methoxy-3-oxo-20,21,22-23,24,25,26,27-octanordammanrane (4), 12β-O-acetyl-15α,17β-dihydroxy-3-oxo-20,21,22-23,24,25,26,27-octanordammanrane (5), and 12β,15α-dihydroxy-3-oxo-17-en-20,21,22-23,24,25,26,27-octanordammanrane (6), together with two known nor-dammarane triterpenoids, 12β-hydroxy-3-oxo-24α-methoxy- 25,26,27-trinordammara-20,24-epoxy (7) and 3β,12β-dihydroxy-23,24,25,26,27- hexanordammarane-20-one (8). The structures of the isolated compounds were established based on 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated compounds were tested in vitro for cytotoxic potential against seven tumor cell lines and radical scavenging activities. Compounds 46 exhibited significant cytotoxic activities against all tested tumor cell lines and radical scavenging activities against ABTS·+ radicals comparable with the standard drug Trolox. Full article
(This article belongs to the Special Issue Triterpenes and Triterpenoids 2013)
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1379 KiB  
Article
Induction of Apoptosis by Costunolide in Bladder Cancer Cells is Mediated through ROS Generation and Mitochondrial Dysfunction
by Azhar Rasul, Rui Bao, Mahadev Malhi, Bing Zhao, Ichiro Tsuji, Jiang Li and Xiaomeng Li
Molecules 2013, 18(2), 1418-1433; https://doi.org/10.3390/molecules18021418 - 24 Jan 2013
Cited by 93 | Viewed by 7216
Abstract
Despite the availability of several therapeutic options, a safer and more effective modality is urgently needed for treatment of bladder cancer. Costunolide, a member of sesquiterpene lactone family, possesses potent anticancer properties. In this study, for the first time we investigated the effects [...] Read more.
Despite the availability of several therapeutic options, a safer and more effective modality is urgently needed for treatment of bladder cancer. Costunolide, a member of sesquiterpene lactone family, possesses potent anticancer properties. In this study, for the first time we investigated the effects of costunolide on the cell viability and apoptosis in human bladder cancer T24 cells. Treatment of T24 cells with costunolide resulted in a dose-dependent inhibition of cell viability and induction of apoptosis which was associated with the generation of ROS and disruption of mitochondrial membrane potential (Δψm). These effects were significantly blocked when the cells were pretreated with N-acetyl- cysteine (NAC), a specific ROS inhibitor. Exposure of T24 cells to costunolide was also associated with increased expression of Bax, down-regulation of Bcl-2, survivin and significant activation of caspase-3, and its downstream target PARP. These findings provide the rationale for further in vivo and clinical investigation of costunolide against human bladder cancer. Full article
(This article belongs to the Section Natural Products Chemistry)
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239 KiB  
Article
Cytotoxicity and Anti-Inflammatory Activity of Methylsulfanyl-triazoloquinazolines
by Rashad A. Al-Salahi, Amira M. Gamal-Eldeen, Amer M. Alanazi, Mohamed A. Al-Omar, Mohamed A. Marzouk and Moustafa M. G. Fouda
Molecules 2013, 18(2), 1434-1446; https://doi.org/10.3390/molecules18021434 - 24 Jan 2013
Cited by 8 | Viewed by 5003 | Retraction
Abstract
A series of twenty five 2-methylsulfanyl-[1,2,4]triazolo[1,5-a]quinazoline derivatives 125 was previously synthesized. We have now investigated their cytotoxic effects against hepatocellular Hep-G2 and colon HCT-116 carcinoma cells and effect on the macrophage growth, in addition to their influence of the [...] Read more.
A series of twenty five 2-methylsulfanyl-[1,2,4]triazolo[1,5-a]quinazoline derivatives 125 was previously synthesized. We have now investigated their cytotoxic effects against hepatocellular Hep-G2 and colon HCT-116 carcinoma cells and effect on the macrophage growth, in addition to their influence of the inflammatory mediators [nitric oxide (NO), tumor necrosis factor-α (TNF-α), prostaglandin E-2 (PGE-2) and in bacterial lipopolysachharide (LPS)-stimulated macrophages]. The findings revealed that compounds 13 and 17 showed the highest cytotoxicity and that 3, 68 and 25 are promising multi-potent anti-inflammatory agents. Full article
(This article belongs to the Section Medicinal Chemistry)
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298 KiB  
Article
Degradation Kinetics of Atorvastatin under Stress Conditions and Chemical Analysis by HPLC
by Marcelo Antonio Oliveira, Maria Irene Yoshida, Valdenir José Belinelo and Romanélia Spessemille Valotto
Molecules 2013, 18(2), 1447-1456; https://doi.org/10.3390/molecules18021447 - 24 Jan 2013
Cited by 27 | Viewed by 7507
Abstract
Atorvastatin is an antilipemic drug belonging to the statins class, whose reference drug is Pfizer’s Lipitor®. It is used to reduce the levels of lipoproteins rich in cholesterol and reduce the risk of coronary artery disease. It is well-known that calcium [...] Read more.
Atorvastatin is an antilipemic drug belonging to the statins class, whose reference drug is Pfizer’s Lipitor®. It is used to reduce the levels of lipoproteins rich in cholesterol and reduce the risk of coronary artery disease. It is well-known that calcium atorvastatin (ATV), C66H68CaF2N4O10•3H2O, presents polymorphism. The drug in question is commonly sought after by pharmaceutical industries that produce generic drugs, due to the fact that the drug has a high value price, it is consumed globally, and its patent expired in late 2010. Many questions concerning this drug’s pharmaceutical scope demonstrate its importance regarding stability studies and the identification of degradation products of drugs and pharmaceutical formulations. ATV has been found to degrade under acid and basic conditions, including a first order kinetic degradation under acid conditions, as compared to a zero order kinetic degradation under basic conditions, which tends to be less stable when studied within acid mediums. The rate constant (k) for degradation in acid medium was 1.88 × 10−2 s−1 (first order), while for basic medium k = 2.35 × 10−4 mol L−1 s−1 (zero order), demonstrating a lower stability of the drug within acid mediums. Full article
(This article belongs to the Section Medicinal Chemistry)
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234 KiB  
Article
Degradation of Methyl Blue Using Fe-Tourmaline as a Novel Photocatalyst
by Xuesen Bian, Jianqiu Chen and Rong Ji
Molecules 2013, 18(2), 1457-1463; https://doi.org/10.3390/molecules18021457 - 24 Jan 2013
Cited by 9 | Viewed by 3919
Abstract
This study investigated the photocatalytic activity of tourmaline by itself. Under irradiation of a 13 W, 254 nm UV lamp, 50% of methyl blue disappeared in the presence of 130 mg·L−1 tourmaline. The reaction was inhibited by the addition of ethanol, Cl [...] Read more.
This study investigated the photocatalytic activity of tourmaline by itself. Under irradiation of a 13 W, 254 nm UV lamp, 50% of methyl blue disappeared in the presence of 130 mg·L−1 tourmaline. The reaction was inhibited by the addition of ethanol, Cl, SO42− and Cu2+, and promoted a little by addition of 50 mg/L Mg2+, which supports the inference of involvement of OH radicals. This is the first proposal of tourmaline as a single photocatalyst without the need to add any artificial chemical products. Results from this study might contribute to the broadened usage of this mineral to approach the goals of saving energy and eliminate direct or indirect environmental pollution. Full article
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272 KiB  
Article
Crystal Structure, Antibacterial and Cytotoxic Activities of a New Complex of Bismuth(III) with Sulfapyridine
by Ivana M. Marzano, Marina S. Franco, Priscila P. Silva, Rodinei Augusti, Geandson C. Santos, Nelson G. Fernandes, Mônica Bucciarelli-Rodriguez, Edmar Chartone-Souza and Elene C. Pereira-Maia
Molecules 2013, 18(2), 1464-1476; https://doi.org/10.3390/molecules18021464 - 24 Jan 2013
Cited by 29 | Viewed by 6044
Abstract
A new complex of Bi(III) and sulfapyridine was synthesized and characterized by elemental analysis, atomic absorption spectrometry, conductivity analysis, electrospray ionization mass spectrometry (ESI-MS), infrared spectroscopy, and single crystal X-ray diffraction methods. The antimicrobial and the cytotoxic activities of the compound were investigated. [...] Read more.
A new complex of Bi(III) and sulfapyridine was synthesized and characterized by elemental analysis, atomic absorption spectrometry, conductivity analysis, electrospray ionization mass spectrometry (ESI-MS), infrared spectroscopy, and single crystal X-ray diffraction methods. The antimicrobial and the cytotoxic activities of the compound were investigated. Elemental and conductivity analyses are in accordance to the formulation [BiCl3(C11H11N3O2S)3]. The structure of the complex reveals a distorted octahedral geometry around the bismuth atom, which is bound to three sulfonamidic nitrogens from sulfapyridine, acting as a monodentate ligand, and to three chloride ions. The presence of the compound in solution was confirmed by ESI-MS studies. The complex is 3 times more potent than the ligand against Salmonella typhimurium, 4 times against Staphylococcus aureus, Shigella dysenteriae, and Shigella sonnei and 8 times more potent against Pseudomonas aeruginosa and Escherichia coli. The compound inhibits the growth of chronic myelogenous leukemia cells with an IC50 value of 44 μM whereas the free ligand has no effect up to 100 μM. Full article
(This article belongs to the Section Medicinal Chemistry)
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206 KiB  
Article
Two New Derivatives of 2, 5-Dihydroxyphenylacetic Acid from the Kernel of Entada phaseoloides
by Lin Chen, Yong Zhang, Gang Ding, Mingyu Ba, Ying Guo and Zhongmei Zou
Molecules 2013, 18(2), 1477-1482; https://doi.org/10.3390/molecules18021477 - 25 Jan 2013
Cited by 16 | Viewed by 4253
Abstract
Two new aromatic compounds, butyl 2,5-dihydroxyphenylacetate (1) and butyl 2-O-β-D-glucopyranosyloxy-5-dihydroxyphenylacetate (2), together with three known ones, methyl 2,5-dihydroxyphenylacetate (3), ethyl 2,5-dihydroxyphenylacetate (4) and 2-O-β-D-glucopyranosyloxy-5-hydroxyphenylacetic acid (5), were isolated from [...] Read more.
Two new aromatic compounds, butyl 2,5-dihydroxyphenylacetate (1) and butyl 2-O-β-D-glucopyranosyloxy-5-dihydroxyphenylacetate (2), together with three known ones, methyl 2,5-dihydroxyphenylacetate (3), ethyl 2,5-dihydroxyphenylacetate (4) and 2-O-β-D-glucopyranosyloxy-5-hydroxyphenylacetic acid (5), were isolated from the EtOH extract of the kernel of Entada phaseoloides. The structures of the new compounds were elucidated by MS and NMR experiments. Compounds 1, 3 and 4 displayed potent inhibitory activities against HIV-1 replication, with EC50 values of 9.80 μM, 11.70 μM and 9.93 μM, respectively. Full article
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426 KiB  
Article
Synthesis of Thiophene and NO-Curcuminoids for Antiinflammatory and Anti-Cancer Activities
by Mahera M. Ahmed, M. Akram Khan and Kim Drummond Rainsford
Molecules 2013, 18(2), 1483-1501; https://doi.org/10.3390/molecules18021483 - 25 Jan 2013
Cited by 24 | Viewed by 5685
Abstract
In search of better NSAIDs four novel nitric oxide donating derivatives of curcumin (compounds 9ad), and four thiophene curcuminoids (compounds 10ac, 11) have been synthesised. The cytotoxic effects of these compounds along with the lead compound [...] Read more.
In search of better NSAIDs four novel nitric oxide donating derivatives of curcumin (compounds 9ad), and four thiophene curcuminoids (compounds 10ac, 11) have been synthesised. The cytotoxic effects of these compounds along with the lead compound curcumin (7) and their effect on the production of the reactive oxygen species nitric oxide and pro-inflammatory cytokines IL-1β, TNF-α and chemokine CXCL-8 were evaluated using human monocytic THP-1 and colon adenocarcinoma CACO-2 cell lines. All of the nitric oxide donating curcuminoids 9ad and the thiophene curcuminoids 10ac and 11 were non-cytotoxic to THP-1 cells over a concentration range of 10-100 μM and compared with curcumin compounds 10b and 10c, were more toxic. In CACO-2 cells, 10b and 11 appeared to be non-toxic at 10 to 50 μM, whereas 10a and 10c were non-cytotoxic at 10 μM only. These results clearly indicate that the introduction of a nitroxybutyl moiety to curcumin and replacement of phenyl rings with thiophene units reduces the cytotoxic effect of the parent curcumin, whereas a methyl substituted thiophene increases the cytotoxic effects. In THP-1 cells, drugs 10a and 11 significantly decreased IL-1-β production at their non-cytotoxic concentrations, whereas, they did not decrease TNF-α production in CACO-2 cells. Compound 11 showed a significant decrease in CXCL-8 production. Full article
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685 KiB  
Article
Synthesis and Characterization of Novel Dendrons Bearing Amino-Nitro-Substituted Azobenzene Units and Oligo(ethylene glycol) Spacers: Thermal, Optical Properties, Langmuir Blodgett Films and Liquid-Crystalline Behaviour
by Jesús Ortíz-Palacios, Efraín Rodríguez-Alba, Mayra Avelar, Ana Martínez, Maria Del Pilar Carreón-Castro and Ernesto Rivera
Molecules 2013, 18(2), 1502-1527; https://doi.org/10.3390/molecules18021502 - 25 Jan 2013
Cited by 10 | Viewed by 4372
Abstract
In this work, we report the synthesis and characterization of a novel series of first and second generation Fréchet type dendrons bearing amino-nitro substituted azobenzene units and tetra(ethylene glycol) spacers. These compounds were fully characterized by FTIR, 1H and 13C-NMR spectroscopies, [...] Read more.
In this work, we report the synthesis and characterization of a novel series of first and second generation Fréchet type dendrons bearing amino-nitro substituted azobenzene units and tetra(ethylene glycol) spacers. These compounds were fully characterized by FTIR, 1H and 13C-NMR spectroscopies, and their molecular weights were determined by MALDI-TOF-MS. The thermal properties of the obtained dendrons were studied by TGA and DSC and their optical properties by absorption spectroscopy in solution and cast film. Molecular calculations were performed in order to determine the optimized geometries of these molecules in different environments. Besides, Langmuir and Langmuir Blodgett films were prepared with the first generation dendrons that were shown to be amphiphilic. Finally, some of the dendrons showed a liquid crystalline behaviour, which was studied by light polarized microscopy as a function of the temperature in order to determine the transition temperatures and the structure of the mesophase. Full article
(This article belongs to the Section Molecular Diversity)
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335 KiB  
Article
Oxygen Radical Absorbance Capacity of Different Varieties of Strawberry and the Antioxidant Stability in Storage
by Chunyang Li, Wu-Yang Huang, Xing-Na Wang and Wen-Xu Liu
Molecules 2013, 18(2), 1528-1539; https://doi.org/10.3390/molecules18021528 - 25 Jan 2013
Cited by 18 | Viewed by 4816
Abstract
Total antioxidant capacity of different varieties of strawberry (Ningfeng, Ningyu, Zijin 4, Toyonoka, Benihope, Sweet Charlie) in different developmental stages (including green unripe stages, half red stages, and red ripe stages) was investigated by oxygen radical absorbance capacity (ORAC) assay. In addition, effects [...] Read more.
Total antioxidant capacity of different varieties of strawberry (Ningfeng, Ningyu, Zijin 4, Toyonoka, Benihope, Sweet Charlie) in different developmental stages (including green unripe stages, half red stages, and red ripe stages) was investigated by oxygen radical absorbance capacity (ORAC) assay. In addition, effects of the antioxidant properties of strawberry stored at 4 °C or −18 °C for a period of five months were studied. The results showed that antioxidant capacity of strawberry changed based on tested part, developmental stage, variety, and time of collection. Calyces had significantly higher ORAC values compared with fruits. Strawberry fruits had higher ORAC values during the green unripe stages than the half red stages and red ripe stages. Strawberries got higher ORAC values during short-time storage, and then decreased during long-time storage. Samples stored at −18 °C exhibited higher antioxidant capacity than those stored at 4 °C, while vacuum treatment could further increase ORAC values. The results indicated the potential market role of strawberries as a functional food and could provide great value in preventing oxidation reaction in food processing and storage for the dietary industry. Full article
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221 KiB  
Communication
Original TDAE Strategy Using Propargylic Chloride: Rapid Access to 1,4-Diarylbut-3-ynol Derivatives
by Manon Roche, Thierry Terme and Patrice Vanelle
Molecules 2013, 18(2), 1540-1548; https://doi.org/10.3390/molecules18021540 - 25 Jan 2013
Cited by 6 | Viewed by 4267
Abstract
We report herein the first synthesis of propargylic alcohols using an organic reducing agent. Diarylbutynol derivatives are formed in moderate to good yields under mild conditions from the reaction of 1-(3-chloroprop-1-ynyl)-4-nitrobenzene with various aromatic aldehydes using tetrakis(dimethylamino)ethylene (TDAE) as reductant. Full article
(This article belongs to the Section Organic Chemistry)
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714 KiB  
Article
Fruit Coloration and Anthocyanin Biosynthesis after Bag Removal in Non-Red and Red Apples (Malus × domestica Borkh.)
by Yulian Liu, Fei Che, Lixin Wang, Rui Meng, Xiaojun Zhang and Zhengyang Zhao
Molecules 2013, 18(2), 1549-1563; https://doi.org/10.3390/molecules18021549 - 25 Jan 2013
Cited by 77 | Viewed by 6341
Abstract
In the present study, evolution of apple color (L* and a/b), the accumulation of anthocyanins and the activity of the related enzymes, phenylalanine ammonia-lyase (PAL), chalcone isomerase (CHI), dihydroflavonol4-reductase (DFR) and UDP-Glucose: flavonoid-3-O-galactosyl transferase (UFGT), were investigated in bagged non-red apple [...] Read more.
In the present study, evolution of apple color (L* and a/b), the accumulation of anthocyanins and the activity of the related enzymes, phenylalanine ammonia-lyase (PAL), chalcone isomerase (CHI), dihydroflavonol4-reductase (DFR) and UDP-Glucose: flavonoid-3-O-galactosyl transferase (UFGT), were investigated in bagged non-red apple cultivars (‘Granny Smith’ and ‘Golden Delicious’) and red apple cultivars (‘Starkrimon’ and ‘Pink Lady’). Young fruits were bagged 40–45 days after flowering (DAF), and fruits of ‘Golden Delicious’ and ‘Starkrimon’ were uncovered and exposed to light 120 DAF, while those of ‘Granny Smith’ and ‘Pink Lady’ were exposed for 160 DAF. Results showed that cyanidin 3-galactoside (cy3-gal) was the most abundant anthocyanin in both non-red and red cultivars. Level of anthocyanins was higher in ‘Granny Smith’ than in ‘Golden Delicious’, indicating that red color was easier to develop in green cultivar ‘Granny Smith’ than in yellow cultivar ‘Golden Delicious’ after bag removal. The cy3-gal accumulation of non-red cultivars tested was not significantly correlated with PAL, CHI and DFR activity, but was significantly correlated with UFGT activity. During the reddening of non-red apples, UFGT may be the more important factor in the anthocyanin biosynthesis. Full article
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559 KiB  
Article
Synergism of Antifungal Activity between Mitochondrial Respiration Inhibitors and Kojic Acid
by Jong H. Kim, Bruce C. Campbell, Kathleen L. Chan, Noreen Mahoney and Ronald P. Haff
Molecules 2013, 18(2), 1564-1581; https://doi.org/10.3390/molecules18021564 - 25 Jan 2013
Cited by 24 | Viewed by 5867
Abstract
Co-application of certain types of compounds to conventional antimicrobial drugs can enhance the efficacy of the drugs through a process termed chemosensitization. We show that kojic acid (KA), a natural pyrone, is a potent chemosensitizing agent of complex III inhibitors disrupting the mitochondrial [...] Read more.
Co-application of certain types of compounds to conventional antimicrobial drugs can enhance the efficacy of the drugs through a process termed chemosensitization. We show that kojic acid (KA), a natural pyrone, is a potent chemosensitizing agent of complex III inhibitors disrupting the mitochondrial respiratory chain in fungi. Addition of KA greatly lowered the minimum inhibitory concentrations of complex III inhibitors tested against certain filamentous fungi. Efficacy of KA synergism in decreasing order was pyraclostrobin > kresoxim-methyl > antimycin A. KA was also found to be a chemosensitizer of cells to hydrogen peroxide (H2O2), tested as a mimic of reactive oxygen species involved in host defense during infection, against several human fungal pathogens and Penicillium strains infecting crops. In comparison, KA-mediated chemosensitization to complex III inhibitors/H2O2 was undetectable in other types of fungi, including Aspergillus flavus, A. parasiticus, and P. griseofulvum, among others. Of note, KA was found to function as an antioxidant, but not as an antifungal chemosensitizer in yeasts. In summary, KA could serve as an antifungal chemosensitizer to complex III inhibitors or H2O2 against selected human pathogens or Penicillium species. KA-mediated chemosensitization to H2O2 seemed specific for filamentous fungi. Thus, results indicate strain- and/or drug-specificity exist during KA chemosensitization. Full article
(This article belongs to the Section Natural Products Chemistry)
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579 KiB  
Article
Extraction of Antioxidant Components from Bidens pilosa Flowers and Their Uptake by Human Intestinal Caco-2 Cells
by Wen-Chin Lee, Chiung-Chi Peng, Chi-Huang Chang, Shiau-Huei Huang and Charng-Cherng Chyau
Molecules 2013, 18(2), 1582-1601; https://doi.org/10.3390/molecules18021582 - 25 Jan 2013
Cited by 20 | Viewed by 6922
Abstract
Bidens pilosa L. var. radiata (BPR, Asteraceae) is a commonly used folk medicine for treating various disorders such as diabetes, inflammation and hypertension. Recent studies to determine its chemical composition have revealed three di-O-caffeoylquinic acids (DiCQAs) and three polyacetylene glucosides (PGAs) [...] Read more.
Bidens pilosa L. var. radiata (BPR, Asteraceae) is a commonly used folk medicine for treating various disorders such as diabetes, inflammation and hypertension. Recent studies to determine its chemical composition have revealed three di-O-caffeoylquinic acids (DiCQAs) and three polyacetylene glucosides (PGAs) to be among the major bioactive markers. To obtain the major compounds of these two chemical classes, the ethyl acetate fraction (EM) obtained using liquid-liquid partition from the methanol extract resulted in a fraction with the highest total phenolic and total flavonoid contents and antioxidant activities in radical scavenging and ferric reducing power assays. To assess the bioavailability of EM, we examined the in vitro uptake using the Caco-2 human colonic cell line. The apparent permeability coefficient (Papp) for each of the compounds within PGAs measured in both apical (AP) to basolateral (BL) and BL to AP was found to preferentially appear BL to AP direction, indicated that a basolateral to apical efflux system was detected in the study. DiCQAs had a lower efflux ratio than those from PGAs (2.32–3.67 vs. 6.03–78.36). Thus, it strongly implies that most of the DiCQAs are better absorbed than the PGAs. Full article
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332 KiB  
Article
An Efficient Microwave-Assisted Suzuki Reaction using a New Pyridine-Pyrazole/Pd(II) Species as Catalyst in Aqueous Media
by Liqun Shen, Suyu Huang, Yuanmei Nie and Fuhou Lei
Molecules 2013, 18(2), 1602-1612; https://doi.org/10.3390/molecules18021602 - 25 Jan 2013
Cited by 23 | Viewed by 4970
Abstract
A new pyridine-pyrazole N–N ligand has been conveniently synthesized and characterized by 1H-, 13C-NMR, IR spectroscopies, HRMS and X-ray single-crystal crystallography analyses. The ligand adds to palladium(II) under basic conditions to give high yields of an air-stable and water-soluble complex that [...] Read more.
A new pyridine-pyrazole N–N ligand has been conveniently synthesized and characterized by 1H-, 13C-NMR, IR spectroscopies, HRMS and X-ray single-crystal crystallography analyses. The ligand adds to palladium(II) under basic conditions to give high yields of an air-stable and water-soluble complex that was fully characterized by NMR and HRMS. The complex was investigated as a catalyst for the Suzuki reaction in aqueous media under microwave irradiation. The compound proved to be an effective catalyst. Full article
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223 KiB  
Article
Microwave-Assisted Improved Synthesis of Pyrrolo[2,3,4-kl]acridine and Dihydropyrrolo[2,3,4-kl]acridine Derivatives Catalyzed by Silica Sulfuric Acid
by Chengpao Cao, Changliang Xu, Wei Lin, Xuemei Li, Minghua Hu, Juxian Wang, Zhibin Huang, Daqing Shi and Yucheng Wang
Molecules 2013, 18(2), 1613-1625; https://doi.org/10.3390/molecules18021613 - 28 Jan 2013
Cited by 20 | Viewed by 4164
Abstract
An improved synthesis of multifunctionalized pyrrolo[2,3,4-kl]acridine derivatives with different substituted patterns using silica sulfuric acid (SSA) as a heterogeneous catalyst under microwave irradiation conditions was developed. The reaction could be conducted by using readily available and inexpensive substrates within short periods [...] Read more.
An improved synthesis of multifunctionalized pyrrolo[2,3,4-kl]acridine derivatives with different substituted patterns using silica sulfuric acid (SSA) as a heterogeneous catalyst under microwave irradiation conditions was developed. The reaction could be conducted by using readily available and inexpensive substrates within short periods of 12–15 min. under microwave irradiation. Compared with the conventional methods, the remarkable advantages of this method are milder reaction conditions, operational simplicity, higher yields, short reaction times, and an environmentally friendly procedure. Full article
(This article belongs to the Section Organic Chemistry)
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269 KiB  
Article
Diastereoselective [2+2] Photocycloaddition of Chiral Cyclic Enones with Olefins in Aqueous Media Using Surfactants
by Yasuhiro Nishiyama, Mikiko Shibata, Takuya Ishii, Tsumoru Morimoto, Hiroki Tanimoto, Ken Tsutsumi and Kiyomi Kakiuchi
Molecules 2013, 18(2), 1626-1637; https://doi.org/10.3390/molecules18021626 - 28 Jan 2013
Cited by 8 | Viewed by 5485
Abstract
We conducted diastereodifferentiating [2+2] photocycloadditions of cyclo-hexenones modified with a chiral 8-(p-methoxy phenyl)menthyl auxiliary with olefins in water. Although the photoreaction didn’t proceed at all in pure water owing to very low solubility, the use of surfactants [sodium dodecyl sulfate (SDS) [...] Read more.
We conducted diastereodifferentiating [2+2] photocycloadditions of cyclo-hexenones modified with a chiral 8-(p-methoxy phenyl)menthyl auxiliary with olefins in water. Although the photoreaction didn’t proceed at all in pure water owing to very low solubility, the use of surfactants [sodium dodecyl sulfate (SDS) or dodecylamine hydrochloride (DAH)] and additive (organic solvent) enabled the reactions to progress with moderate to high conversions and yields. Furthermore, we synthesized a new menthol derivative substrate containing a (p-octyloxy)phenyl group for enhancing hydrophobicity, and elucidated that this new substrate was found to be a suitable chiral auxiliary in this asymmetric photoreaction in aqueous system. The additive effect of organic molecules on the yield and diastereoselectivity of the photo-adducts is also discussed. Full article
(This article belongs to the Special Issue New Trends in Photochemistry)
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817 KiB  
Article
Use of Pyrogallol Red and Pyranine as Probes to Evaluate Antioxidant Capacities towards Hypochlorite
by Fernanda Pérez-Cruz, Contanza Cortés, Elias Atala, Pamela Bohle, Francisco Valenzuela, Claudio Olea-Azar, Hernán Speisky, Alexis Aspée, Eduardo Lissi, Camilo López-Alarcón and Raquel Bridi
Molecules 2013, 18(2), 1638-1652; https://doi.org/10.3390/molecules18021638 - 28 Jan 2013
Cited by 11 | Viewed by 5653
Abstract
Hypochlorite is a strong oxidant able to induce deleterious effects in biological systems. The goal of this work was to investigate the use of PGR and PYR as probes in assays aimed at evaluating antioxidant activities towards hypochorite and apply it to plant [...] Read more.
Hypochlorite is a strong oxidant able to induce deleterious effects in biological systems. The goal of this work was to investigate the use of PGR and PYR as probes in assays aimed at evaluating antioxidant activities towards hypochorite and apply it to plant extracts employed in Chilean folk medicine. The consumption of PGR and PYR was evaluated from the decrease in the visible absorbance and fluorescence intensity, respectively. Total phenolic content was determined by the Folin Ciocalteau assay. PGR and PYR react with hypochlorite with different kinetics, being considerably faster the consumption of PGR. Different stoichiometric values were also determined: 0.7 molecules of PGR and 0.33 molecules of PYR were bleached per each molecule of added hypochlorite. Both probes were protected by antioxidants, but the rate of PGR bleaching was too fast to perform a kinetic analysis. For PYR, the protection took place without changes in its initial consumption rate, suggesting a competition between the dye and the antioxidant for hypochlorite. Plant extracts protected PYR giving a PYR-HOCl index that follows the order: Fuchsia magellanica » Marrubium vulgare » Tagetes minuta > Chenopodium ambrosoides » Satureja montana > Thymus praecox. Based on both the kinetic data and the protection afforded by pure antioxidants, we selected PYR as the best probe. The proposed methodology allows evaluating an antioxidant capacity index of plant extracts related to the reactivity of the samples towards hypochlorite. Full article
(This article belongs to the Section Natural Products Chemistry)
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187 KiB  
Article
Graphite-Supported Perchloric Acid (HClO4-C): An Efficient and Recyclable Heterogeneous Catalyst for the One-Pot Synthesis of Amidoalkyl Naphthols
by Zhen-Kai Lei, Li Xiao, Xiao-Quan Lu, He Huang and Chen-Jiang Liu
Molecules 2013, 18(2), 1653-1659; https://doi.org/10.3390/molecules18021653 - 28 Jan 2013
Cited by 19 | Viewed by 4957
Abstract
An efficient and direct protocol for the preparation of amidoalkylnaphthols employing a multi-component, one-pot condensation reaction of 2-naphthol, aromatic aldehydes and acetamide or benzamide in the presence of graphite supported perchloric acid under solvent-free conditions is described. The thermal solvent-free procedure offers advantages [...] Read more.
An efficient and direct protocol for the preparation of amidoalkylnaphthols employing a multi-component, one-pot condensation reaction of 2-naphthol, aromatic aldehydes and acetamide or benzamide in the presence of graphite supported perchloric acid under solvent-free conditions is described. The thermal solvent-free procedure offers advantages such as simple work-up, shorter reaction times and higher product yields, and the catalyst exhibited remarkable reactivity and can be recycled. Full article
(This article belongs to the Section Organic Chemistry)
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551 KiB  
Article
Production of Polygalacturonases by Aspergillus section Nigri Strains in a Fixed Bed Reactor
by Marília Maciel, Cristiane Ottoni, Cledir Santos, Nelson Lima, Keila Moreira and Cristina Souza-Motta
Molecules 2013, 18(2), 1660-1671; https://doi.org/10.3390/molecules18021660 - 28 Jan 2013
Cited by 18 | Viewed by 5140
Abstract
Polygalacturonases (PG) are pectinolytic enzymes that have technological, functional and biological applications in food processing, fruit ripening and plant-fungus interactions, respectively. In the present, a microtitre plate methodology was used for rapid screening of 61 isolates of fungi from Aspergillus section Nigri to [...] Read more.
Polygalacturonases (PG) are pectinolytic enzymes that have technological, functional and biological applications in food processing, fruit ripening and plant-fungus interactions, respectively. In the present, a microtitre plate methodology was used for rapid screening of 61 isolates of fungi from Aspergillus section Nigri to assess production of endo- and exo-PG. Studies of scale-up were carried out in a fixed bed reactor operated under different parameters using the best producer strain immobilised in orange peels. Four experiments were conducted under the following conditions: the immobilised cells without aeration; immobilised cells with aeration; immobilised cells with aeration and added pectin; and free cells with aeration. The fermentation was performed for 168 h with removal of sample every 24 h. Aspergillus niger strain URM 5162 showed the highest PG production. The results obtained indicated that the maximum endo- and exo-PG activities (1.18 U·mL−1 and 4.11 U·mL−1, respectively) were obtained when the reactor was operating without aeration. The microtitre plate method is a simple way to screen fungal isolates for PG activity detection. The fixed bed reactor with orange peel support and using A. niger URM 5162 is a promising process for PG production at the industrial level. Full article
(This article belongs to the Section Natural Products Chemistry)
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1050 KiB  
Article
The Passiflora tripartita (Banana Passion) Fruit: A Source of Bioactive Flavonoid C-Glycosides Isolated by HSCCC and Characterized by HPLC–DAD–ESI/MS/MS
by Mario J. Simirgiotis, Guillermo Schmeda-Hirschmann, Jorge Bórquez and Edward J. Kennelly
Molecules 2013, 18(2), 1672-1692; https://doi.org/10.3390/molecules18021672 - 28 Jan 2013
Cited by 128 | Viewed by 11166
Abstract
The banana passion fruit (Passiflora tripartita Breiter, Passifloraceae) known as “tumbo” is very appreciated in tropical and subtropical countries of South America. Methanolic extracts from peel and the fruit juice of P. tripartita growing in Chile were analyzed for antioxidant capacity as [...] Read more.
The banana passion fruit (Passiflora tripartita Breiter, Passifloraceae) known as “tumbo” is very appreciated in tropical and subtropical countries of South America. Methanolic extracts from peel and the fruit juice of P. tripartita growing in Chile were analyzed for antioxidant capacity as well as for flavonoid and phenolic content. A chromatographic method was developed for the rapid identification of the main phenolics in the samples by HPLC-DAD and HPLC-MS. The fast fingerprint analysis allowed the detection of eighteen flavonoid C-glycosides and four flavonoid O-glycoside derivatives which were characterized by UV spectra and ESI-MS-MS analysis. Several of the C-glycosides detected are structurally related to the orientin derivative 4′-methoxy-luteolin-8-C-(6″acetyl)-b-D-glucopyranoside (31), fully elucidated by spectroscopic methods. The antioxidant derivative 31 along with schaftoside, vicenin II, orientin and vitexin were isolated from the fruit extract by high-speed countercurrent chromatography (HSCCC). A suitable method for the preparative isolation of flavonol C-glycosides from “tumbo” extracts by HSCCC is reported. The pulp of the fruits showed good antioxidant capacity (12.89 ± 0.02 mg/mL in the DPPH assay). The peel presented the highest content of flavonoids (56.03 ± 4.34 mg quercetin/100 g dry weight) which is related to the highest antioxidant power (10.41 ± 0.01 mg/mL in the DPPH assay). Full article
(This article belongs to the Section Natural Products Chemistry)
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359 KiB  
Article
The Synthesis and Evaluation of Novel Hydroxyl Substituted Chalcone Analogs with in Vitro Anti-Free Radicals Pharmacological Activity and in Vivo Anti-Oxidation Activity in a Free Radical-Injury Alzheimer’s Model
by Ying Pan, Yicun Chen, Qingnan Li, Xiaoyu Yu, Jinzhi Wang and Jinhong Zheng
Molecules 2013, 18(2), 1693-1703; https://doi.org/10.3390/molecules18021693 - 28 Jan 2013
Cited by 27 | Viewed by 5883
Abstract
Alzheimer’s disease (AD) pathogenesis involves an imbalance between free radical formation and destruction. In order to obtain a novel preclinical anti-AD drug candidate, we synthesized a series of novel hydroxyl chalcone analogs which possessed anti-free radical activity, and screened their effects on scavenging [...] Read more.
Alzheimer’s disease (AD) pathogenesis involves an imbalance between free radical formation and destruction. In order to obtain a novel preclinical anti-AD drug candidate, we synthesized a series of novel hydroxyl chalcone analogs which possessed anti-free radical activity, and screened their effects on scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) and OH free radicals in vitro. Compound C7, 4,2'-dihydroxy-3,5-dimethoxychalcone was found to have potent activity in these anti-free radical activity tests. Further research revealed that C7 could elevate glutathione peroxidase (GSH-PX) and super oxide dismutase (SOD) levels and lower malonaldehyde (MDA) level in vivo in the Alzheimer’s model. The indication of C7’s effect on AD needs further study. Full article
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259 KiB  
Article
Sinapyl Alcohol Derivatives from the Lipo-soluble Part of Dichrocephala benthamii C. B. Clarke
by Xinhui Tian, Gang Ding, Chaozhong Peng, Yanbao Hu, Li Li, Hong Chen and Zhongmei Zou
Molecules 2013, 18(2), 1720-1727; https://doi.org/10.3390/molecules18021720 - 29 Jan 2013
Cited by 7 | Viewed by 3716
Abstract
Four new sinapyl alcohol derivatives dichrocephols A–D (compounds 14) were isolated from the lipo-soluble part of the whole herb of Dichrocephala benthamii C. B. Clarke, together with the known compound syringenin isovalerate (5). Their structures were elucidated on [...] Read more.
Four new sinapyl alcohol derivatives dichrocephols A–D (compounds 14) were isolated from the lipo-soluble part of the whole herb of Dichrocephala benthamii C. B. Clarke, together with the known compound syringenin isovalerate (5). Their structures were elucidated on the basis of spectroscopic analysis. Their absolute configurations were established by the method of alkaline hydrohysis. Compounds 13 showed moderate cytotoxity against HeLa cells, with IC50 values of 14.8 μM, 51.6 μM and 81.6 μM, respectively. This is the first time that sinapyl alcohol derivatives were isolated from the genus Dichrocephala. Full article
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202 KiB  
Article
Anti-Mycobacterial Activity of Marine Fungus-Derived 4-Deoxybostrycin and Nigrosporin
by Cong Wang, Juan Wang, Yuhong Huang, Hong Chen, Yan Li, Lili Zhong, Yi Chen, Shengping Chen, Jun Wang, Juling Kang, Yi Peng, Bin Yang, Yongcheng Lin, Zhigang She and Xiaomin Lai
Molecules 2013, 18(2), 1728-1740; https://doi.org/10.3390/molecules18021728 - 29 Jan 2013
Cited by 40 | Viewed by 7857
Abstract
4-Deoxybostrycin is a natural anthraquinone compound isolated from the Mangrove endophytic fungus Nigrospora sp. collected from the South China Sea. Nigrosporin is the deoxy-derivative of 4-deoxybostrycin. They were tested against mycobacteria, especially Mycobacterium tuberculosis. In the Kirby-Bauer disk diffusion susceptibility test, they [...] Read more.
4-Deoxybostrycin is a natural anthraquinone compound isolated from the Mangrove endophytic fungus Nigrospora sp. collected from the South China Sea. Nigrosporin is the deoxy-derivative of 4-deoxybostrycin. They were tested against mycobacteria, especially Mycobacterium tuberculosis. In the Kirby-Bauer disk diffusion susceptibility test, they both had inhibition zone sizes of over 25 mm. The results of the absolute concentration susceptibility test suggested that they had inhibitory effects against mycobacteria. Moreover, 4-deoxybostrycin exhibited good inhibition which was even better than that of first line anti-tuberculosis (TB) drugs against some clinical multidrug-resistant (MDR) M. tuberculosis strains. The gene expression profile of M. tuberculosis H37Rv after treatment with 4-deoxybostrycin was compared with untreated bacteria. One hundred and nineteen out of 3,875 genes were significantly different in M. tuberculosis exposed to 4-deoxybostrycin from control. There were 46 functionally known genes which are involved in metabolism, information storage and processing and cellular processes. The differential expressions of six genes were further confirmed by quantitative real-time polymerase chain reaction (qRT-PCR). The present study provides a useful experiment basis for exploitation of correlative new drugs against TB and for finding out new targets of anti-mycobacterial therapy. Full article
(This article belongs to the Section Natural Products Chemistry)
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1979 KiB  
Article
Ganoderma tsugae Hepatoprotection against Exhaustive Exercise-Induced Liver Injury in Rats
by Chi-Chang Huang, Wen-Ching Huang, Suh-Ching Yang, Chih-Chi Chan and Wan-Teng Lin
Molecules 2013, 18(2), 1741-1754; https://doi.org/10.3390/molecules18021741 - 29 Jan 2013
Cited by 32 | Viewed by 5646
Abstract
Several studies have been shown that accelerated apoptosis is involved in post-exercise lymphocytopenia and tissue damage after high-intensity exercise. Ganoderma tsugae (GT) is one of the well-known medicinal mushrooms that possess various pharmacological functions. This mushroom has traditionally been used for health promotion [...] Read more.
Several studies have been shown that accelerated apoptosis is involved in post-exercise lymphocytopenia and tissue damage after high-intensity exercise. Ganoderma tsugae (GT) is one of the well-known medicinal mushrooms that possess various pharmacological functions. This mushroom has traditionally been used for health promotion purposes. This study investigates the hepatoprotective effects of GT on exhaustive exercise-induced liver damage. Twenty-four male Sprague-Dawley rats were randomly divided into four groups and designated as exhaustive exercise only (E), exhaustive exercise with low dosage (EL), medium dosage (EM) and high dosage (EH) GT at 0, 0.1875, 0.9375 and 1.875 g/kg/day, respectively. After 30 days all rats were euthanized immediately after an exhaustive running challenge on a motorized treadmill. The rat livers were immediately harvested. Evidence of apoptotic liver cell death was revealed using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and caspases mediated cascade events. DNA fragmentation, an apoptosis process, can be examined using TUNEL assay. A few TUNEL-positive hepatocytes, compared to the exercise only group, were observed in the livers from exhaustive animals supplemented with GT. Immunoblot analysis also showed that caspase-6-mediated specific cleavage of lamin A/C was increased significantly in the livers of group E, but was significantly decreased in the EM and EH groups. Our observations demonstrate that GT possesses anti-apoptotic and hepatoprotective potential after exhaustive exercise. Full article
(This article belongs to the Section Natural Products Chemistry)
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195 KiB  
Article
Microwave-Enhanced Cross-Coupling Reactions Involving Alkynyltrifluoroborates with Aryl Bromides
by Vitali Coltuclu, Eric Dadush, Abhijit Naravane and George W. Kabalka
Molecules 2013, 18(2), 1755-1761; https://doi.org/10.3390/molecules18021755 - 29 Jan 2013
Cited by 1 | Viewed by 3977
Abstract
Palladium-catalyzed alkynylation has emerged as one of the most reliable methods for the synthesis of alkynes which are often used in natural product syntheses and material science. An efficient method for coupling alkynyltrifluoroborates with various aryl bromides in the presence of a palladium [...] Read more.
Palladium-catalyzed alkynylation has emerged as one of the most reliable methods for the synthesis of alkynes which are often used in natural product syntheses and material science. An efficient method for coupling alkynyltrifluoroborates with various aryl bromides in the presence of a palladium catalyst has been developed using microwave irradiation. The microwave reactions are rapid and efficient. Full article
(This article belongs to the Special Issue Organoboron Chemistry)
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919 KiB  
Article
Antioxidant Capacity of Two Novel Bioactive Fe(III)-Cyclophane Complexes
by Alex J. Salazar-Medina, Rocío Sugich-Miranda, Eli Teran-Cabanillas, Jesús Hernández, Gustavo A. González-Aguilar, Enrique Rudiño-Piñera, Rogerio R. Sotelo-Mundo and Enrique F. Velázquez-Contreras
Molecules 2013, 18(2), 1762-1774; https://doi.org/10.3390/molecules18021762 - 29 Jan 2013
Cited by 9 | Viewed by 4850
Abstract
The cyclophanes 2,9,25,32-tetraoxo-4,7,27,30-tetrakis(carboxymethyl)-1,4,7,10, 24,27,30,33-octaaza-17,40-dioxa[10.1.10.1]paracyclophane (PO) and 2,9,25,32-tetraoxo-4,7,27,30-tetrakis(carboxymethyl)-1,4,7,10,24,27,30,33-octaaza[10.1.10.1]paracyclophane (PC) were coordinated with iron to form cationic binuclear Fe(III) Fe2PO and Fe2PC complexes, respectively. Their antioxidant capacity, superoxide dismutase and peroxidase mimetic activity, as well as their [...] Read more.
The cyclophanes 2,9,25,32-tetraoxo-4,7,27,30-tetrakis(carboxymethyl)-1,4,7,10, 24,27,30,33-octaaza-17,40-dioxa[10.1.10.1]paracyclophane (PO) and 2,9,25,32-tetraoxo-4,7,27,30-tetrakis(carboxymethyl)-1,4,7,10,24,27,30,33-octaaza[10.1.10.1]paracyclophane (PC) were coordinated with iron to form cationic binuclear Fe(III) Fe2PO and Fe2PC complexes, respectively. Their antioxidant capacity, superoxide dismutase and peroxidase mimetic activity, as well as their toxicity toward peripheral blood mononuclear cells (PBMCs) were evaluated. Both Fe2PO and Fe2PC are interesting biomimetics with antioxidant capacity similar to that of ascorbic acid that prevent mortality in cultured PBMCs, with the potential to have bioactive and protective functions in disease animal models. Full article
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292 KiB  
Article
Effects of Adenosine Extract from Pholiota adiposa (Fr.) Quel on mRNA Expressions of Superoxide Dismutase and Immunomodulatory Cytokines
by Chang Rong Wang, Wen Tao Qiao, Ye Ni Zhang and Fang Liu
Molecules 2013, 18(2), 1775-1782; https://doi.org/10.3390/molecules18021775 - 29 Jan 2013
Cited by 11 | Viewed by 4530
Abstract
Pholiota adiposa is a kind of edible mushroom which has long been known for its health care applications. To reveal the exact mechanism of its protective functions in humans, in this study we isolated and identified the active compound PB3 of P. [...] Read more.
Pholiota adiposa is a kind of edible mushroom which has long been known for its health care applications. To reveal the exact mechanism of its protective functions in humans, in this study we isolated and identified the active compound PB3 of P. adiposa for the first time by a combination of chromatography techniques, including NKA macroporous resin and Sephadex G-15. PB3, with molecular mass of 267.2 Da and molecular formula of C10H13N5O4 discovered by mass spectrum (MS) was identified to be adenosine. Mice were injected intraperitoneally with purified fraction PB3. Seven days after injection, we found a 1.5-fold increase of IL10 at the mRNA level, while a down regulated expression of IL-2, IL-6 and IFN-γ to 49.0%, 56.9% and 73.4%, respectively, was detected in spleen by real-time quantitative PCR. What’s more, SOD expression level was significantly increased by 1.6-fold compared to control. Fraction PB3 displayed anti-inflammatory potency and heightened SOD activity on the transcriptional level, which could be considered of further pharmaceutical or medication value. Full article
(This article belongs to the Section Natural Products Chemistry)
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689 KiB  
Article
Improvement of Ylang-Ylang Essential Oil Characterization by GC×GC-TOFMS
by Michał Brokl, Marie-Laure Fauconnier, Céline Benini, Georges Lognay, Patrick Du Jardin and Jean-François Focant
Molecules 2013, 18(2), 1783-1797; https://doi.org/10.3390/molecules18021783 - 30 Jan 2013
Cited by 36 | Viewed by 9453
Abstract
A single fraction of essential oil can often contain hundreds of compounds. Despite of the technical improvements and the enhanced selectivity currently offered by the state-of-the-art gas chromatography (GC) and mass spectrometry (MS) instruments, the complexity of essential oils is frequently underestimated. Comprehensive [...] Read more.
A single fraction of essential oil can often contain hundreds of compounds. Despite of the technical improvements and the enhanced selectivity currently offered by the state-of-the-art gas chromatography (GC) and mass spectrometry (MS) instruments, the complexity of essential oils is frequently underestimated. Comprehensive two-dimensional GC coupled to time-of-flight MS (GC×GC-TOFMS) was used to improve the chemical characterization of ylang-ylang essential oil fractions recently reported in a previous one-dimensional (1D) GC study. Based on both, the enhanced chromatographic separation and the mass spectral deconvolution, 161 individual compounds were identified and labeled as potentially characteristic analytes found in both low and high boiling fractions issued from distillation of mature ylang-ylang flowers. Compared to the most recent full GC-MS characterization, this represents 75 new compounds, essentially consisting of terpenes, terpenoid esters, and alcohols. Full article
(This article belongs to the Section Natural Products Chemistry)
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280 KiB  
Article
Radical Scavenging Capacity of Methanolic Phillyrea latifolia L. Extract: Anthocyanin and Phenolic Acids Composition of Fruits
by Erol Ayranci and Naciye Erkan
Molecules 2013, 18(2), 1798-1810; https://doi.org/10.3390/molecules18021798 - 30 Jan 2013
Cited by 13 | Viewed by 4507
Abstract
Radical scavenging capacity of a crude methanolic extract from the fruits of Phillyrea latifolia L., commonly known as green olive tree or mock privet, was investigated with reference to anthocyanin standards, as flavonoids, and phenolic acid standards, as phenylpropanoids. Characterization with high performance [...] Read more.
Radical scavenging capacity of a crude methanolic extract from the fruits of Phillyrea latifolia L., commonly known as green olive tree or mock privet, was investigated with reference to anthocyanin standards, as flavonoids, and phenolic acid standards, as phenylpropanoids. Characterization with high performance liquid chromatography-diode array detection (HPLC-DAD) indicated the presence of keracyanin, kuromanin, cyanidin, ferulic acid, caffeic acid and rosmarinic acid at amounts of 289.1, 90.4, 191.4, 225.2, 221.2 and 190.1 mg/100 g fresh weight (FW) of fruits, respectively. Chlorogenic and p-coumaric acids were found to exist in lower amounts. Trolox equivalent antioxidant capacity (TEAC) and IC50 values of the plant extract were found to be 1.8 mM Trolox equivalents (TE)/g FW of fruits and 69.4 µg/mL, respectively, indicating the close radical scavenging activity of the extract to those of keracyanin and p-coumaric acid. The crude methanolic P. latifolia L. fruit extract was seen to be fairly potent in radical scavenging. Total phenolic content (TPC) of the plant extract was found to be 1652.9 mg gallic acid equivalent (GAE)/100 g FW of fruits. Full article
(This article belongs to the Section Natural Products Chemistry)
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220 KiB  
Article
Study of Total Antioxidant Activity of Human Serum Blood in the Pathology of Alcoholism
by Elena I. Korotkova, Wolfhardt Freinbichler, Wolfgang Linert, Elena V. Dorozhko, Mariya V. Bukkel, Evgeniy V. Plotnikov and Olesya A. Voronova
Molecules 2013, 18(2), 1811-1818; https://doi.org/10.3390/molecules18021811 - 30 Jan 2013
Cited by 10 | Viewed by 4745
Abstract
The total antioxidant activity (TAA) of human serum blood of patients suffering from alcoholism was tested by cathode voltammetry with a model process of oxygen electroreduction. A known spectrophotometrical method was used for comparison. As results the total antioxidant activity of serum blood [...] Read more.
The total antioxidant activity (TAA) of human serum blood of patients suffering from alcoholism was tested by cathode voltammetry with a model process of oxygen electroreduction. A known spectrophotometrical method was used for comparison. As results the total antioxidant activity of serum blood of patients with alcoholism was estimated by voltammetry during therapy in hospital. It was shown the TAA of serum blood of patients in pathology before and after treatment is lower than that one of healthy people. However, during the process of 10 days of alcoholism treatment the TAA coefficient increases. The relationship between the coefficient of total antioxidant activity of human serum blood and the stage of treatment was detected. Full article
(This article belongs to the Special Issue Antioxidants 2012)
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640 KiB  
Article
Two New Koumine-Type Indole Alkaloids from Gelsemium elegans Benth.
by Mingxue Sun, Xiaoli Hou, Huanhuan Gao, Junsheng Guo and Kai Xiao
Molecules 2013, 18(2), 1819-1825; https://doi.org/10.3390/molecules18021819 - 31 Jan 2013
Cited by 12 | Viewed by 4872
Abstract
Two new indole alkaloids, 21-oxokoumine (1) and furanokoumine (2), were isolated from the roots of Gelsemium elegans Benth together with three known compounds. The structures of the two novel compounds were elucidated by spectroscopic methods, including NMR, HR-ESI-MS, UV, [...] Read more.
Two new indole alkaloids, 21-oxokoumine (1) and furanokoumine (2), were isolated from the roots of Gelsemium elegans Benth together with three known compounds. The structures of the two novel compounds were elucidated by spectroscopic methods, including NMR, HR-ESI-MS, UV, IR, CD and molecular modeling. Compound 1 is the first instance of a koumine-type alkaloid with a carbonyl at the C-21 position, while compound 2 possesses a tetrahydrofuran ring located on C-20 and C-21. Full article
(This article belongs to the Section Natural Products Chemistry)
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220 KiB  
Article
Development and Molecular Characterization of 55 Novel Polymorphic cDNA-SSR Markers in Faba Bean (Vicia faba L.) Using 454 Pyrosequencing
by Sundan Suresh, Jong-Hyun Park, Gyu-Taek Cho, Ho-Sun Lee, Hyung-Jin Baek, Sok-Young Lee and Jong-Wook Chung
Molecules 2013, 18(2), 1844-1856; https://doi.org/10.3390/molecules18021844 - 31 Jan 2013
Cited by 34 | Viewed by 5242
Abstract
Faba bean (Vicia faba L.) is a major food source and fodder legume, popularly known for its high content of seed-protein. Its role is critical in crop rotation, and for fixing nitrogen effectively. Polymorphic simple sequence repeat markers from transcript sequences (cDNA; [...] Read more.
Faba bean (Vicia faba L.) is a major food source and fodder legume, popularly known for its high content of seed-protein. Its role is critical in crop rotation, and for fixing nitrogen effectively. Polymorphic simple sequence repeat markers from transcript sequences (cDNA; simple sequence repeat [SSR]) were developed for faba bean (Vicia faba). We found that 1,729 SSR loci from 81,333 individual sequence reads and 240 primer pairs were designed and synthesized. In total, 55 primer pairs were found to be polymorphic and scorable consistently when screened in 32 accessions. The number of alleles ranged from 2 to 15, frequency of major alleles per locus varied from 0.17 to 0.91, the genotypes number ranged from 2 to 17, observed and expected heterozycosity values ranged from 0.00 to 0.44 and 0.17 to 0.89 and overall PIC values ranged from 0.16 to 0.88 respectively. These markers will be a useful tool for assessing the genetic diversity, understanding the population structure, and breeding patterns of faba bean. Full article
(This article belongs to the Section Molecular Diversity)
282 KiB  
Article
Seasonal Difference in Antioxidant Capacity and Active Compounds Contents of Eucommia ulmoides Oliver Leaf
by Qiang Zhang, Yinquan Su and Jingfang Zhang
Molecules 2013, 18(2), 1857-1868; https://doi.org/10.3390/molecules18021857 - 1 Feb 2013
Cited by 51 | Viewed by 4983
Abstract
Leaf of Eucommia ulmoides Oliver (EU) is a Traditional Chinese Medicine and a functional food in China. Antioxidant contents of EU leaves, which were collected monthly during the period of May–October in three years, were determined. Samples’ antioxidant capacity was characterized by DPPH [...] Read more.
Leaf of Eucommia ulmoides Oliver (EU) is a Traditional Chinese Medicine and a functional food in China. Antioxidant contents of EU leaves, which were collected monthly during the period of May–October in three years, were determined. Samples’ antioxidant capacity was characterized by DPPH radical scavenging activity, hydroxyl radical scavenging activity, ferrous chelating ability, and antioxidant capacity in linoleic acid emulsion and in rapeseed oil assays. The results showed that contents of some active compounds and antioxidant activity were related to a certain time of the year. Samples collected in August showed high content of phenolics, and the samples collected in May contained higher amount of flavonoids than other samples. Leaves collected in May or June exhibited high contents of rutin, quercetin, geniposidic acid and aucubin. The August leaves showed stable and high DPPH radical scavenging activity, and ferrous chelating ability. May samples showed strong inhibitory effects on oxidation of rapeseed oil and linoleic acid. The DPPH radical scavenging activity was related to the total phenolics content. Flavonoids played an important role in the inhibitory effects on rapeseed oil and linoleic acid oxidation. Therefore, August and May were indicated as the best months to harvest EU leaves for industry. Full article
(This article belongs to the Section Natural Products Chemistry)
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200 KiB  
Article
Silica-Supported Polyphosphoric Acid in the Synthesis of 4-Substituted Tetrahydroisoquinoline Derivatives
by Stanimir Manolov, Stoyanka Nikolova and Iliyan Ivanov
Molecules 2013, 18(2), 1869-1880; https://doi.org/10.3390/molecules18021869 - 1 Feb 2013
Cited by 8 | Viewed by 5655
Abstract
We report herein an application of an α-amidoalkylation reaction, as an alternative efficient synthesis of 4-aryl- and 4-methyl-1,2,3,4-tetrahydroisoquinoline derivatives. The amides required for this purpose would result from reaction of aminoacetaldehyde dimethylacetal with different substituted benzenes in polyphosphoric acid, followed by acylation of [...] Read more.
We report herein an application of an α-amidoalkylation reaction, as an alternative efficient synthesis of 4-aryl- and 4-methyl-1,2,3,4-tetrahydroisoquinoline derivatives. The amides required for this purpose would result from reaction of aminoacetaldehyde dimethylacetal with different substituted benzenes in polyphosphoric acid, followed by acylation of the obtained amines with different acid chlorides or sulfochlorides. We compared the cyclisation step using conventional (milieu of acetic-trifluoracetic acid = 4:1) and solid supported reagents (SiO2/PPA), as recovered, regenerated and reused without loss of its activity catalyst. We found that in comparison to conventional methods, the yields of the reaction are greater and the reaction time is shorter. Full article
(This article belongs to the Section Organic Chemistry)
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269 KiB  
Article
Synthesis and Antiproliferative Activity of C-3 Functionalized Isobenzofuran-1(3H)-ones
by Róbson Ricardo Teixeira, Gustavo Costa Bressan, Wagner Luiz Pereira, Joana Gasperazzo Ferreira, Fabrício Marques De Oliveira and Deborah Campos Thomaz
Molecules 2013, 18(2), 1881-1896; https://doi.org/10.3390/molecules18021881 - 1 Feb 2013
Cited by 34 | Viewed by 5427
Abstract
A series of thirteen C-3 functionalized isobenzofuran-1(3H)-ones (phtalides) was synthesized via condensation, aromatization, and acetylation reactions. NMR (one and two dimensional experiments), IR, and mass spectrometry analysis allowed confirmation of the identity of the synthesized compounds. The substances were submitted to [...] Read more.
A series of thirteen C-3 functionalized isobenzofuran-1(3H)-ones (phtalides) was synthesized via condensation, aromatization, and acetylation reactions. NMR (one and two dimensional experiments), IR, and mass spectrometry analysis allowed confirmation of the identity of the synthesized compounds. The substances were submitted to in vitro bioassays against U937 (lymphoma) and K562 (myeloid leukemia) cancer cell lines using the MTT cytotoxicity assay. Some derivatives inhibited 90% of cell viability at 100 µM. Also, two phtalides presented biological activity superior than that of etoposide (VP16), a commercial drug used as a positive control in the assays. In silico drug properties of the evaluated compounds were calculated and the results are discussed. Full article
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1180 KiB  
Article
A Pyrene- and Phosphonate-Containing Fluorescent Probe as Guest Molecule in a Host Polymer Matrix
by Elise Villemin, Benjamin Elias, Michel Devillers and Jacqueline Marchand-Brynaert
Molecules 2013, 18(2), 1897-1915; https://doi.org/10.3390/molecules18021897 - 1 Feb 2013
Cited by 3 | Viewed by 5030
Abstract
New host-guest materials have been prepared by incorporation of a home-made organic probe displaying a pyrene motif and a phosphonate function into a regular amphiphilic copolymer. Using powder X-Ray diffraction, photoluminescence and FT-IR spectroscopy, we have been able to study the non-covalent interactions [...] Read more.
New host-guest materials have been prepared by incorporation of a home-made organic probe displaying a pyrene motif and a phosphonate function into a regular amphiphilic copolymer. Using powder X-Ray diffraction, photoluminescence and FT-IR spectroscopy, we have been able to study the non-covalent interactions between the host matrix and the guest molecule in the solid state. Interestingly, we have shown that the matrix directs the guest spatial localization and alters its properties. Thanks to the comparison of pyrene vs. N-pyrenylmaleimide derivatives, the influence of the chemical nature of the guest molecules on the non-covalent interactions with the host have been studied. In addition, using polyethylene glycol as a reference host, we have been able to evidence a true matrix effect within our new insertion materials. The phosphonated guest molecule appears to be a novel probe targeting the hydrophilic domain of the host copolymer. Full article
(This article belongs to the Section Organic Chemistry)
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276 KiB  
Article
Anti-Oxidative and Cholinesterase Inhibitory Effects of Leaf Extracts and Their Isolated Compounds from Two Closely Related Croton Species
by Ashwell R. Ndhlala, Mutalib A. Aderogba, Bhekumthetho Ncube and Johannes Van Staden
Molecules 2013, 18(2), 1916-1932; https://doi.org/10.3390/molecules18021916 - 1 Feb 2013
Cited by 46 | Viewed by 5668
Abstract
A comparative evaluation of the antioxidant and acetylcholinesterase inhibitory activity of the leaf extracts of Croton gratissimus and Croton zambesicus (subgratissimus) and compounds isolated from the extracts was carried out to determine their potential and suitability or otherwise as a substitute [...] Read more.
A comparative evaluation of the antioxidant and acetylcholinesterase inhibitory activity of the leaf extracts of Croton gratissimus and Croton zambesicus (subgratissimus) and compounds isolated from the extracts was carried out to determine their potential and suitability or otherwise as a substitute for each other in the management of oxidative and neurodegenerative conditions. Different antioxidant assays (DPPH, FRAP, β-carotene-linoleic and the lipid peroxidation models) and the microplate assay for acetylcholinesterase (AChE) inhibition were carried out separately to study the activities of the crude leaf extracts and four solvent fractions from each of the two Croton species. Bioassay guided fractionation was used to target antioxidant constituents of the crude extracts and ethyl acetate fractions of 20% aqueous methanol extract of C. gratissimus on silica gel and Sephadex LH-20 columns resulted in the isolation of kaempferol-3-O-β-6''(p-coumaroyl) glucopyranoside (tiliroside, 2), apigenin-6-C-glucoside (isovitexin, 3) and kampferol (4). The extract of C. zambesicus yielded quercetin-3-O-β-6''(p-coumaroyl) glucopyranoside-3'-methyl ether (helichrysoside- 3'-methyl ether, 1), kaempferol-3-O-β-6''(p-coumaroyl) glucopyranoside (tiliroside, 2) and apigenin-6-C-glucoside (isovitexin, 3). Three of the isolated compounds and their different combinations were also included in the bioassays. In all the assays performed, the antioxidant capacity and AChE inhibitory effects of C. zambesicus extracts were weaker than those of C. gratissimus. This suggests that C. gratissimus may not be substituted by C. zambesicus, despite the similarity in some of their constituents. Generally, the combinations made from the isolated compounds showed better activities in most of the assays compared to the individual isolated compounds. This suggests mechanisms such as synergism and/or additive effects to be taking place. This study established low, moderate and high antioxidant activities as well as AChE inhibitory effects by the crude extracts, fractions, compounds and compound combinations. This means some of the extracts, isolated compounds and compound combinations could be useful in the management of neurodegenerative conditions and serve as sources of natural neurodegenerative agents. Full article
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302 KiB  
Article
Design, Synthesis and Hepatoprotective Activity of Analogs of the Natural Product Goodyeroside A
by Feng Zhang, Bei Han, Peng Li, Ziyun Lin, Dali Yin, Yan Li, Jialiang Zhong and Haihong Huang
Molecules 2013, 18(2), 1933-1948; https://doi.org/10.3390/molecules18021933 - 1 Feb 2013
Cited by 2 | Viewed by 5012
Abstract
Goodyeroside A, a natural product isolated from the Goodyera species, possesses significant hepatoprotective activity and has a novel skeleton not previously observed in other synthetic drugs used for the treatment of hepatitis. Herein, we report a highly stereoselective synthesis of goodyeroside A and [...] Read more.
Goodyeroside A, a natural product isolated from the Goodyera species, possesses significant hepatoprotective activity and has a novel skeleton not previously observed in other synthetic drugs used for the treatment of hepatitis. Herein, we report a highly stereoselective synthesis of goodyeroside A and related analogs with varying substituents at the α position of the carbonyl group to explore the structure-activity relationships of goodyeroside A. The absolute configuration of analog 5d was confirmed by single crystal X-ray analysis. The results from in vitro and in vivo studies indicate that 5a, the fully acetylated compound of goodyeroside A, is worthy of further investigation as a lead to identify novel hepatoprotective agents. Full article
(This article belongs to the Section Medicinal Chemistry)
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1553 KiB  
Article
Euphorbia formosana Root Extract Induces Apoptosis by Caspase-Dependent Cell Death via Fas and Mitochondrial Pathway in THP-1 Human Leukemic Cells
by Yi-Jen Hsieh, Chih-Jui Chang, Chin-Feng Wan, Chin-Piao Chen, Yi-Han Chiu, Yann-Lii Leu and Kou-Cheng Peng
Molecules 2013, 18(2), 1949-1962; https://doi.org/10.3390/molecules18021949 - 1 Feb 2013
Cited by 19 | Viewed by 5926
Abstract
Acute myeloid leukemia (AML), a very rare type of cancer, generally affects patients over 50 years old. While clinical drugs to treat advanced stages of AML exist, the disease becomes increasingly resistant to therapies. Euphorbia formosana Hayata (EF) is a native Taiwanese medicinal [...] Read more.
Acute myeloid leukemia (AML), a very rare type of cancer, generally affects patients over 50 years old. While clinical drugs to treat advanced stages of AML exist, the disease becomes increasingly resistant to therapies. Euphorbia formosana Hayata (EF) is a native Taiwanese medicinal plant used to treat rheumatism, liver cirrhosis, herpes zoster, scabies, and photoaging, along with tumor suppression. However, the mechanisms by which it suppresses tumors have not been explored. Here, we provide molecular evidence that a hot-water extract of Euphorbia formosana (EFW) selectively inhibited the growth of human leukemic cancer cells more than other solid human cancer cell lines. Most importantly, the plant extract had limited toxicity toward healthy peripheral blood mononuclear cells (PBMCs). After THP-1 leukemic cells were treated with 50–100 µg/mL EFW for one day, the S phase DNA content of the cells increased, while treatment with 200–400 µg/mL caused the cells to accumulate in the G0/G1 phase. Notably, EFW did not affect A-549 lung cancer cells. The effectiveness of EFW against THP-1 cells may be through caspase-dependent apoptosis in leukemic cells, which is mediated through the Fas and mitochondrial pathways. The potent antileukemic activity of EFW in vitro warrants further investigation of this plant to treat leukemias and other malignancies. Full article
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232 KiB  
Article
Biohybrid -Se-S- Coupling Reactions of an Amino Acid Derived Seleninate
by Mohannad Abdo, Zhexun Sun and Spencer Knapp
Molecules 2013, 18(2), 1963-1972; https://doi.org/10.3390/molecules18021963 - 4 Feb 2013
Cited by 5 | Viewed by 4638
Abstract
We describe the synthesis of the N-(2-seleninatoethyl) amide of N-Boc-phenylalanine, serving here as a peptide model, and its reductive coupling reactions under mild conditions with unprotected thiouridine and glutathione. Selenosulfide products such as these comprise reversibly conjugated bio-components, and can potentially [...] Read more.
We describe the synthesis of the N-(2-seleninatoethyl) amide of N-Boc-phenylalanine, serving here as a peptide model, and its reductive coupling reactions under mild conditions with unprotected thiouridine and glutathione. Selenosulfide products such as these comprise reversibly conjugated bio-components, and can potentially find uses as probes of biological function, such as enzyme inhibitors, delivery systems, or structural mimics. Full article
(This article belongs to the Special Issue Disulfide and Diselenide Chemistry)
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248 KiB  
Article
Synthesis and Characterization of Novel Unsymmetrical and Symmetrical 3-Halo- or 3-Methoxy-substituted 2-Dibenzoylamino-1,4-naphthoquinone Derivatives
by Yakini Brandy, Nailah Brandy, Emmanuel Akinboye, Malik Lewis, Claudia Mouamba, Seshat Mack, Ray J. Butcher, Alan J. Anderson and Oladapo Bakare
Molecules 2013, 18(2), 1973-1984; https://doi.org/10.3390/molecules18021973 - 4 Feb 2013
Cited by 15 | Viewed by 4844
Abstract
Symmetrical and unsymmetrical 3-halo- or 3-methoxy- substituted 2-dibenzoylamino- 1,4-naphthoquinone analogs were synthesized with an average yield of 45% via sodium hydride promoted bis-acylation of 2-amino-3-chloro-1,4-naphthoquinone, 2-amino-3-bromo-1,4-naphthoquinone and 2-amino-3-methoxy-1,4-naphthoquinone. Full article
(This article belongs to the Section Organic Chemistry)
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300 KiB  
Article
Cytotoxicity and Structure-Activity Relationships of Xanthone Derivatives from Mesua beccariana, Mesua ferrea and Mesua congestiflora towards Nine Human Cancer Cell Lines
by Soek Sin Teh, Gwendoline Cheng Lian Ee, Siau Hui Mah, Yang Mooi Lim and Zuraini Ahmad
Molecules 2013, 18(2), 1985-1994; https://doi.org/10.3390/molecules18021985 - 4 Feb 2013
Cited by 30 | Viewed by 5138
Abstract
The cytotoxic structure-activity relationships among a series of xanthone derivatives from Mesua beccariana, Mesua ferrea and Mesua congestiflora were studied. Eleven xanthone derivatives identified as mesuarianone (1), mesuasinone (2), mesuaferrin A (3), mesuaferrin B (4 [...] Read more.
The cytotoxic structure-activity relationships among a series of xanthone derivatives from Mesua beccariana, Mesua ferrea and Mesua congestiflora were studied. Eleven xanthone derivatives identified as mesuarianone (1), mesuasinone (2), mesuaferrin A (3), mesuaferrin B (4), mesuaferrin C (5), 6-deoxyjacareubin (6), caloxanthone C (7), macluraxanthone (8), 1,5-dihydroxyxanthone (9), tovopyrifolin C (10) and α-mangostin (11) were isolated from the three Mesua species. The human cancer cell lines tested were Raji, SNU-1, K562, LS-174T, SK-MEL-28, IMR-32, HeLa, Hep G2 and NCI-H23. Mesuaferrin A (3), macluraxanthone (8) and α-mangostin (11) showed strong cytotoxicities as they possess significant inhibitory effects against all the cell lines. The structure-activity relationship (SAR) study revealed that the diprenyl, dipyrano and prenylated pyrano substituent groups of the xanthone derivatives contributed towards the cytotoxicities. Full article
(This article belongs to the Section Natural Products Chemistry)
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558 KiB  
Article
The Reaction Mechanism of Claisen Rearrangement Obtained by Transition State Spectroscopy and Single Direct-Dynamics Trajectory
by Izumi Iwakura, Yu Kaneko, Shigehiko Hayashi, Atsushi Yabushita and Takayoshi Kobayashi
Molecules 2013, 18(2), 1995-2004; https://doi.org/10.3390/molecules18021995 - 4 Feb 2013
Cited by 14 | Viewed by 4918
Abstract
Chemical bond breaking and formation during chemical reactions can be observed using “transition state spectroscopy”. Comparing the measurement result of the transition state spectroscopy with the simulation result of single direct-dynamics trajectory, we have elucidated the reaction dynamics of Claisen rearrangement of allyl [...] Read more.
Chemical bond breaking and formation during chemical reactions can be observed using “transition state spectroscopy”. Comparing the measurement result of the transition state spectroscopy with the simulation result of single direct-dynamics trajectory, we have elucidated the reaction dynamics of Claisen rearrangement of allyl vinyl ether. Observed the reaction of the neat sample liquid, we have estimated the time constants of transformation from straight-chain structure to aromatic-like six-membered ring structure forming the C1-C6 bond. The result clarifies that the reaction proceeds via three steps taking longer time than expected from the gas phase calculation. This finding provides new hypothesis and discussions, helping the development of the field of reaction mechanism analysis. Full article
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277 KiB  
Article
Antioxidant Activity of the Extracts of Some Cowpea (Vigna unguiculata (L) Walp.) Cultivars Commonly Consumed in Pakistan
by Muhammad Zia-Ul-Haq, Shakeel Ahmad, Ryszard Amarowicz and Vincenzo De Feo
Molecules 2013, 18(2), 2005-2017; https://doi.org/10.3390/molecules18022005 - 5 Feb 2013
Cited by 57 | Viewed by 7364
Abstract
The present investigation has been carried out to determine the antioxidant activity of the methanolic extracts obtained from four cultivars of cowpea (Vigna unguiculata (L) Walp.) seeds. Phenolic compounds present in the extracts showed the antioxidant and antiradical properties when investigated using [...] Read more.
The present investigation has been carried out to determine the antioxidant activity of the methanolic extracts obtained from four cultivars of cowpea (Vigna unguiculata (L) Walp.) seeds. Phenolic compounds present in the extracts showed the antioxidant and antiradical properties when investigated using a linoleic acid peroxidation model, FRAP, ORAC and TRAP assays, as well as DPPH, hydroxyl, nitric oxide and superoxide radical scavenging activity. The HPLC analysis of the cowpea extracts showed the presence of neochlorogenic acid, chlorogenic acid and caffeic acids. The results indicated that methanolic extract of the cowpea resembled in the aforementioned activities those from other leguminous seeds and pulses. Phenolic constituents contained in cowpea may have a future role as ingredients in the development of functional foods. Full article
(This article belongs to the Special Issue Antioxidants 2012)
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1465 KiB  
Article
The Degradation Mechanism of Toxic Atractyloside in Herbal Medicines by Decoction
by Liang-Yu Chen, Anren Hu and Chih-Jui Chang
Molecules 2013, 18(2), 2018-2028; https://doi.org/10.3390/molecules18022018 - 5 Feb 2013
Cited by 13 | Viewed by 5460
Abstract
Atractyloside (ATR) is found in many Asteraceae plants that are commonly used as medicinal herbs in China and other eastern Asian countries. ATR binds specifically to the adenine nucleotide translocator in the inner mitochondrial membrane and competitively inhibits ADP and ATP transport. The [...] Read more.
Atractyloside (ATR) is found in many Asteraceae plants that are commonly used as medicinal herbs in China and other eastern Asian countries. ATR binds specifically to the adenine nucleotide translocator in the inner mitochondrial membrane and competitively inhibits ADP and ATP transport. The toxicity of ATR in medical herbs can be reduced by hydrothermal processing, but the mechanisms of ATR degradation are not well understood. In this study, GC-MS coupled with SPE and TMS derivatisation was used to detect ATR levels in traditional Chinese medicinal herbs. Our results suggest that ATR molecules were disrupted by decomposition, hydrolysis and saponification after heating with water (decoction) for a long period of time. Hydrothermal processing could decompose the endogenous toxic compounds and also facilitate the detoxification of raw materials used in the Chinese medicine industry. Full article
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1073 KiB  
Article
Structural Requirements for the Antifungal Activities of Natural Drimane Sesquiterpenes and Analogues, Supported by Conformational and Electronic Studies
by Marcos Derita, Iván Montenegro, Francisco Garibotto, Ricardo D. Enriz, Mauricio Cuellar Fritis and Susana A. Zacchino
Molecules 2013, 18(2), 2029-2051; https://doi.org/10.3390/molecules18022029 - 5 Feb 2013
Cited by 28 | Viewed by 5216
Abstract
Seventeen drimanes including polygodial (1), isopolygodial (2), drimenol (3) and confertifolin (4) obtained from natural sources and the semi-synthetic derivatives 5–17 obtained from 1–3, were evaluated in vitro for antifungal properties against a unique [...] Read more.
Seventeen drimanes including polygodial (1), isopolygodial (2), drimenol (3) and confertifolin (4) obtained from natural sources and the semi-synthetic derivatives 5–17 obtained from 1–3, were evaluated in vitro for antifungal properties against a unique panel of fungi with standardized procedures by using two end-points, MIC100 and MIC50. A SAR analysis of the whole series, supported by conformational and electronic studies, allowed us to show that the Δ7,8 -double bond would be one of the key structural features related to the antifungal activity. The MEPs obtained for active compounds exhibit a clear negative minimum value (deep red zone) in the vicinity of the Δ7,8 -double bond, which is not present in the inactive ones. Apart of this negative zone, a positive region (deep blue) appears in 1, which is not observed either in its epimer 2 nor in the rest of the active compounds. The LogP of active compounds varies between 2.33 and 3.84, but differences in MICs are not correlated with concomitant variations in LogP values. Full article
(This article belongs to the Section Natural Products Chemistry)
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537 KiB  
Article
Evaluation of the Anti-Inflammatory Effect of Chalcone and Chalcone Analogues in a Zebrafish Model
by Yau-Hung Chen, Wei-Hua Wang, Yun-Hsin Wang, Zi-Yu Lin, Chi-Chung Wen and Ching-Yuh Chern
Molecules 2013, 18(2), 2052-2060; https://doi.org/10.3390/molecules18022052 - 5 Feb 2013
Cited by 45 | Viewed by 6510
Abstract
The aim of this study was to investigate novel chalcones with potent anti-inflammatory activities in vivo. Chalcone and two chalcone analogues (compound 5 and 9) were evaluated using a caudal fin-wounded transgenic zebrafish line “Tg(mpx:gfp)” to visualize [...] Read more.
The aim of this study was to investigate novel chalcones with potent anti-inflammatory activities in vivo. Chalcone and two chalcone analogues (compound 5 and 9) were evaluated using a caudal fin-wounded transgenic zebrafish line “Tg(mpx:gfp)” to visualize the effect of neutrophil recruitment dynamically. Results showed that treatment with compound 9 not only affected wound-induced neutrophil recruitment, but also affected Mpx enzymatic activity. Moreover, protein expression levels of pro-inflammatory factors (Mpx, NFκB, and TNFα) were also regulated by compound 9. Taken together, our results provide in vivo evidence of the anti-inflammatory effects of synthesized chalcone analogues on wound-induced inflammation. Full article
(This article belongs to the Section Medicinal Chemistry)
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1499 KiB  
Article
Antioxidant Capacity and HPLC-DAD-MS Profiling of Chilean Peumo (Cryptocarya alba) Fruits and Comparison with German Peumo (Crataegus monogyna) from Southern Chile
by Mario J. Simirgiotis
Molecules 2013, 18(2), 2061-2080; https://doi.org/10.3390/molecules18022061 - 5 Feb 2013
Cited by 96 | Viewed by 7921
Abstract
Liquid chromatography (LC) coupled with UV detection and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the generation of chemical fingerprints and the identification of phenolic compounds in peumo fruits and aerial parts from southern Chile. Thirty three compounds (19 of [...] Read more.
Liquid chromatography (LC) coupled with UV detection and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the generation of chemical fingerprints and the identification of phenolic compounds in peumo fruits and aerial parts from southern Chile. Thirty three compounds (19 of these detected in C. alba and 23 in C. monogyna) were identified, mainly flavonoid glycosides, phenolic acids, anthocyanins and flavonoid aglycons. Total phenolic content and total flavonoid content was measured for both species, and were higher in the extracts from C. monogyna fruits and aerial parts than extracts from C. alba. The fruits of Cryptocarya alba (Chilean peumo) presented high antioxidant capacity (9.12 ± 0.01 mg/mL in the DPPH assay), but was three times lower to that of Crataegus monogyna (German peumo) (3.61 ± 0.01 mg/mL in the DPPH assay). Full article
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223 KiB  
Article
The Reaction of Ethyl 2-oxo-2H-chromene-3-carboxylate with Hydrazine Hydrate
by Hatem A. Abdel-Aziz, Tilal Elsaman, Mohamed I. Attia and Amer M. Alanazi
Molecules 2013, 18(2), 2084-2095; https://doi.org/10.3390/molecules18022084 - 6 Feb 2013
Cited by 17 | Viewed by 13810
Abstract
Although salicylaldehyde azine (3) was reported in 1985 as the single product of the reaction of ethyl 2-oxo-2H-chromene-3-carboxylate (1) with hydrazine hydrate, we identified another main reaction product, besides 3, which was identified as malono-hydrazide ( [...] Read more.
Although salicylaldehyde azine (3) was reported in 1985 as the single product of the reaction of ethyl 2-oxo-2H-chromene-3-carboxylate (1) with hydrazine hydrate, we identified another main reaction product, besides 3, which was identified as malono-hydrazide (4). In the last two decades, however, some articles have claimed that this reaction afforded exclusively hydrazide 2 and they have reported the use of this hydrazide 2 as a precursor in the syntheses of several heterocyclic compounds and hydrazones 6. We reported herein a study of the formation of 2 and a facile route for the synthesis of the target compounds N'-arylidene-2-oxo-2H-chromene-3-carbohydrazides 6af. Full article
(This article belongs to the Section Organic Chemistry)
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324 KiB  
Article
Palladium-Catalyzed Amination of Dichloroquinolines with Adamantane-Containing Amines
by Anton S. Abel, Alexei D. Averin, Olga A. Maloshitskaya, Evgenii N. Savelyev, Boris S. Orlinson, Ivan A. Novakov and Irina P. Beletskaya
Molecules 2013, 18(2), 2096-2109; https://doi.org/10.3390/molecules18022096 - 6 Feb 2013
Cited by 10 | Viewed by 5360
Abstract
Pd-catalyzed amination of isomeric 2,6-, 2,8-, 4,8- and 4,7-dichloroquinolines was studied using adamantane-containing amines in which substituents at the nitrogen atom differ in bulkiness. The selectivity of the amination of 2,6-dichloroquinoline was very low, substantially better results were obtained with 2,8-dichloroquinoline, and 4,8- [...] Read more.
Pd-catalyzed amination of isomeric 2,6-, 2,8-, 4,8- and 4,7-dichloroquinolines was studied using adamantane-containing amines in which substituents at the nitrogen atom differ in bulkiness. The selectivity of the amination of 2,6-dichloroquinoline was very low, substantially better results were obtained with 2,8-dichloroquinoline, and 4,8- and 4,7-dichloroquinolines provided the best yields of the amination products. Diamination of 4,8- and 4,7-dichloroquinolines was carried out with two amines which differ strongly in the bulkiness of the alkyl group. In the majority of cases BINAP ligand was successfully applied, however, it had to be replaced with DavePhos in certain reactions when using the most sterically hindered amine as well as for the diamination reactions. Full article
(This article belongs to the Special Issue Advances in Heteroaromatic Chemistry)
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317 KiB  
Article
Simultaneous Determination of Multiple Sesquiterpenes in Curcuma wenyujin Herbal Medicines and Related Products with One Single Reference Standard
by Jing-Jing Zhu, Yue-Wei An, Guang Hu, Guo-Ping Yin, Qi-Wei Zhang and Zhi-Min Wang
Molecules 2013, 18(2), 2110-2121; https://doi.org/10.3390/molecules18022110 - 6 Feb 2013
Cited by 24 | Viewed by 5199
Abstract
Some Curcuma species are widely used as herbal medicines. Sesquiterpenes are their important bioactive compounds and their quantitative analysis is generally accomplished by gas chromatography (GC) or high performance liquid chromatography (HPLC), but the instability and high cost of some sesquiterpene reference standards [...] Read more.
Some Curcuma species are widely used as herbal medicines. Sesquiterpenes are their important bioactive compounds and their quantitative analysis is generally accomplished by gas chromatography (GC) or high performance liquid chromatography (HPLC), but the instability and high cost of some sesquiterpene reference standards have limited their application. It is necessary to find a practicable means to control the quality of herbal medicines. Using one stable component contained in Curcuma species to determine multiple analogues should be a practical option. In this study, a simple HPLC method for determination of sesquiterpenes using relative response factors (RRFs) has been developed. The easily available and stable active component curdione was selected as the reference compound for calculating the RRFs of the other eight sesquiterpenes, including zedoarondiol (Zedo), isozedoarondiol (Isoz), aerugidiol (Aeru), (4S,5S)-(+)-germacrone-4,5-epoxide (Epox), curcumenone (Curc), neocurdione (Neoc), germacrone (Germ) and furanodiene (Fura). Their RRFs against curdione were between 0.131–1.301, with a good reproducibility. By using the RRFs, the quantification of sesquiterpenes in Curcuma wenyujin herbal medicines and related products was carried out. The method is especially useful for the determination of (4S,5S)-(+)-germacrone-4,5-epoxide, curcumenone, germacrone and furanodiene, which often are regarded as the principle components in Curcuma species, but unstable when were purified. It is an ideal means to analyze the components for which reference standards are not readily available. Full article
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503 KiB  
Article
PF2401-SF, Standardized Fraction of Salvia miltiorrhiza, Induces Apoptosis of Activated Hepatic Stellate Cells in Vitro and in Vivo
by Daya Ram Parajuli, Eun-Jeon Park, Xian-Hua Che, Wen-Yi Jiang, Youn-Chul Kim, Dong Hwan Sohn and Sung Hee Lee
Molecules 2013, 18(2), 2122-2134; https://doi.org/10.3390/molecules18022122 - 6 Feb 2013
Cited by 13 | Viewed by 4858
Abstract
During the course of our attempts to develop a potential herbal medicine, we had previously prepared PF2401-SF, a standardized fraction of S. miltiorrhiza, and reported its hepatoprotective activity in vitro as well as in vivo. Since apoptosis of activated hepatic stellate [...] Read more.
During the course of our attempts to develop a potential herbal medicine, we had previously prepared PF2401-SF, a standardized fraction of S. miltiorrhiza, and reported its hepatoprotective activity in vitro as well as in vivo. Since apoptosis of activated hepatic stellate cells (HSCs) is a well-accepted anti-fibrotic strategy, in this study, we investigated the direct effect of PF2401-SF on t-HSC/Cl-6 cells in vitro and on CCl4-induced liver injury in vivo. We evaluated the activation and cleavage of hallmarkers of apoptosis, namely, caspase 3, 8, 9 and PARP. Upregulation of the pro-apoptotic Bax protein and downregulation of the anti-apoptotic Bcl2 protein were also analyzed. Furthermore, in the PF2401-SF treated rats, apoptosis induction of activated HSCs was demonstrated by reduced distribution of α-SMA-positive cells and the presence of high number of TUNEL-positive cells in vivo. Our data suggest that PF2401-SF can mediate HSCs apoptosis induction, and may be a potential herbal medicine for the treatment of liver fibrosis. Full article
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249 KiB  
Article
Anti-Helicobacter pylori and Urease Inhibition Activities of Some Traditional Medicinal Plants
by Muhammad Amin, Farooq Anwar, Fauqia Naz, Tahir Mehmood and Nazamid Saari
Molecules 2013, 18(2), 2135-2149; https://doi.org/10.3390/molecules18022135 - 7 Feb 2013
Cited by 89 | Viewed by 10260
Abstract
Different parts of Acacia nilotica (L.) Delile, Calotropis procera (Aiton) W.T. Aiton, Adhatoda vasica Nees, Fagoniaar abica L. and Casuarina equisetifolia L. are traditionally used in folk medicine for the treatment of a variety of common ailments like nausea, cold, cough, [...] Read more.
Different parts of Acacia nilotica (L.) Delile, Calotropis procera (Aiton) W.T. Aiton, Adhatoda vasica Nees, Fagoniaar abica L. and Casuarina equisetifolia L. are traditionally used in folk medicine for the treatment of a variety of common ailments like nausea, cold, cough, asthma, fevers, diarrhea, sore throat, swelling, etc. The present study was aimed to evaluate the anti-Helicobacter pylori and urease inhibition activities of extracts produced from the above selected medicinal plants native to Soon Valley (home to an old civilization) in the Punjab province of Pakistan. Methanol, acetone and water extracts of the plants were evaluated for anti-bacterial activity against thirty four clinical isolates and two reference strains of H. pylori. Minimum inhibitory concentrations (MICs) of the extracts were determined using the agar dilution method and compared with some standard antibiotics like amoxicillin (AMX), clarithromycin (CLA), tetracycline (TET) and metronidazole (MNZ), used in the triple therapy for H. pylori eradication. H. pylori urease inhibition activity of the extracts was assessed by the phenol red method, wherein, Lineweaver-Burk plots were used to determine Michaelis-Menten constants for elucidating the mechanism of inhibition. Methanol and acetone extracts from Acacia nilotica and Calotropis procera exhibited stronger anti-H. pylori activity than MNZ, almost comparable activity with TET, but were found to be less potent than AMX and CLT. The rest of the extracts exhibited lower activity than the standard antibiotics used in this study. In the H. pylori urease inhibitory assay, methanol and acetone extracts of Acacia nilotica and Calotropis procera showed significant inhibition. Lineweaver-Burk plots indicated a competitive mechanism for extract of Acacia nilotica, whereas extract of Calotropis procera exhibited a mixed type of inhibition. Full article
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231 KiB  
Article
Volatiles and Water- and Fat-Soluble Precursors of Saanen Goat and Cross Suffolk Lamb Flavour
by Marta Madruga, Ingrid Dantas, Angela Queiroz, Luciana Brasil and Yuri Ishihara
Molecules 2013, 18(2), 2150-2165; https://doi.org/10.3390/molecules18022150 - 7 Feb 2013
Cited by 27 | Viewed by 5537
Abstract
This paper evaluates the concentrations of water- and fat-soluble precursors of meat flavour, with the aim of characterising the effect of species on the volatile profile of grilled goat and lamb meat. Compared to goat, lamb meat had higher levels of saturated fatty [...] Read more.
This paper evaluates the concentrations of water- and fat-soluble precursors of meat flavour, with the aim of characterising the effect of species on the volatile profile of grilled goat and lamb meat. Compared to goat, lamb meat had higher levels of saturated fatty acids—SFA, monounsaturated fatty acids—MUFA and polyunsaturated fatty acids—PUFA and similar levels of sugars and free amino acids, except for lysine and glycine, which were higher in goat. Major differences were detected in lipid-derived volatiles; only pyrazine, thiazole, and some Strecker aldehydes were at different concentrations in these species. Volatile compounds derived from the oxidation of linoleic acid were at higher levels in meat from lamb due to the higher concentration of the latter, while compounds formed from α-linolenic acid were at higher levels in goat. It can be concluded that lamb meat has a stronger flavour profile compared to goat meat because it has the highest concentrations of lipid-derived volatile compounds, primarily straight saturated alkanals, pyrazines and thiazole. Full article
491 KiB  
Article
Antibacterial/Antifungal Activity and Synergistic Interactions between Polyprenols and Other Lipids Isolated from Ginkgo Biloba L. Leaves
by Ran Tao, Cheng-Zhang Wang and Zhen-Wu Kong
Molecules 2013, 18(2), 2166-2182; https://doi.org/10.3390/molecules18022166 - 7 Feb 2013
Cited by 85 | Viewed by 8031
Abstract
Polyprenols separated from lipids are promising new components from Ginkgo biloba L. leaves (GBL). In this paper, ginkgo lipids were isolated by extraction with petroleum ether, saponification, and molecular distillation. Eight known compounds: isophytol (1), nerolidol (2), linalool ( [...] Read more.
Polyprenols separated from lipids are promising new components from Ginkgo biloba L. leaves (GBL). In this paper, ginkgo lipids were isolated by extraction with petroleum ether, saponification, and molecular distillation. Eight known compounds: isophytol (1), nerolidol (2), linalool (3), β-sitosterol acetate (4), β-sitosterol (5), stigmasterol (6), ergosterol (7), β-sitosterol-3-O-β-D-glucopyranoside (8) and Ginkgo biloba polyprenols (GBP) were separated from GBL by chromatography and identified mainly by NMR. The separated and identified compounds 1, 2 and 3 are reported here for the first time in GBL. The 3D-DAD-HPLC-chromatogram (190–232 nm) of GBP was recorded. This study provides new evidence as there are no previous reports on antibacterial/antifungal activities and synergistic interactions between GBP and the compounds separated from GBL lipids against Salmonella enterica, Staphylocococus aureus and Aspergillus niger. Nerolidol (2) showed the highest activity among all the tested samples and of all mixture groups tested the GBP with isophytol (1) mixture had the strongest synergistic effect against Salmonella enterica among the three tested strains. A proportion of isophytol and GBP of 38.19%:61.81% (wt/wt) was determined by mixture design as the optimal proportion for the synergistic effect of GBP with isophytol against Salmonella enterica. Full article
(This article belongs to the Section Natural Products Chemistry)
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834 KiB  
Article
Anti-Escherichia coli O157:H7 Properties of Purple Prairie Clover and Sainfoin Condensed Tannins
by Xiu-Li Liu, Yong-Qing Hao, Long Jin, Zhong-Jun Xu, Tim A. McAllister and Yuxi Wang
Molecules 2013, 18(2), 2183-2199; https://doi.org/10.3390/molecules18022183 - 8 Feb 2013
Cited by 56 | Viewed by 5728
Abstract
Condensed tannins (CT) from purple prairie clover (PPC; Dalea purpurea Vent.) and sainfoin (SF; Onobrychis viciifolia) were assessed for anti-Escherichia coli activity by comparing their ability to react with proteins and liposome, cause cell aggregation, and alter outer membrane (OM) morphology [...] Read more.
Condensed tannins (CT) from purple prairie clover (PPC; Dalea purpurea Vent.) and sainfoin (SF; Onobrychis viciifolia) were assessed for anti-Escherichia coli activity by comparing their ability to react with proteins and liposome, cause cell aggregation, and alter outer membrane (OM) morphology and permeability. The PPC CT had greater (P < 0.01) protein-precipitating capacity than SF CT using either bovine serum albumin or ribulose 1,5-disphosphate carboxylase as model proteins. Minimum inhibitory concentration of PPC CT for two strains of E. coli and five strains of E. coli O157:H7 was four to six times lower than that of SF CT. E. coli exposed to 10 µg/mL of both CT had higher (P < 0.05) OM permeability than controls and was greater (P < 0.05) for PPC than for SF CT. Addition of both CT at 50 and 200 µg/mL caused cell aggregation which was more evident (P < 0.05) for PPC than for SF CT. Transmission electron microscopy showed electron dense material on the cell surface when cells were exposed to 50 µg/mL of PPC CT. The greater anti-E. coli activity of PPC than SF CT was due to its enhanced ability to precipitate protein that increased OM permeability and promoted cell aggregation. Full article
(This article belongs to the Section Natural Products Chemistry)
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269 KiB  
Article
Gelam Honey Protects against Gamma-Irradiation Damage to Antioxidant Enzymes in Human Diploid Fibroblasts
by Tengku Ahbrizal Farizal Tengku Ahmad, Zakiah Jubri, Nor Fadilah Rajab, Khairuddin Abdul Rahim, Yasmin Anum Mohd Yusof and Suzana Makpol
Molecules 2013, 18(2), 2200-2211; https://doi.org/10.3390/molecules18022200 - 11 Feb 2013
Cited by 23 | Viewed by 5542
Abstract
The present study was designed to determine the radioprotective effects of Malaysian Gelam honey on gene expression and enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) of human diploid fibroblasts (HDFs) subjected to gamma-irradiation. Six groups of HDFs were [...] Read more.
The present study was designed to determine the radioprotective effects of Malaysian Gelam honey on gene expression and enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) of human diploid fibroblasts (HDFs) subjected to gamma-irradiation. Six groups of HDFs were studied: untreated control, irradiated HDFs, Gelam honey-treated HDFs and HDF treated with Gelam honey pre-, during- and post-irradiation. HDFs were treated with 6 mg/mL of sterilized Gelam honey (w/v) for 24 h and exposed to 1 Gray (Gy) of gamma rays at the dose rate of 0.25 Gy/min. Gamma-irradiation was shown to down-regulate SOD1, SOD2, CAT and GPx1 gene expressions (p < 0.05). Conversely, HDFs treated with Gelam honey alone showed up-regulation of all genes studied. Similarly, SOD, CAT and GPx enzyme activities in HDFs decreased with gamma-irradiation and increased when cells were treated with Gelam honey (p < 0.05). Furthermore, of the three different stages of study treatment, pre-treatment with Gelam honey caused up-regulation of SOD1, SOD2 and CAT genes expression and increased the activity of SOD and CAT. As a conclusion, Gelam honey modulates the expression of antioxidant enzymes at gene and protein levels in irradiated HDFs indicating its potential as a radioprotectant agent. Full article
(This article belongs to the Section Natural Products Chemistry)
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193 KiB  
Article
An Efficient Chemoselective Reduction of Furan Series Unsaturated Dinitriles
by Pavel Bobal and Janette Bobalova
Molecules 2013, 18(2), 2212-2221; https://doi.org/10.3390/molecules18022212 - 11 Feb 2013
Cited by 7 | Viewed by 6324
Abstract
An efficient reduction of double bonds conjugated with nitrile groups and acid or base sensitive furan rings with 2-phenylbenzimidazoline generated in situ has been successfully accomplished with high yields and excellent selectivity. The employed reducing agent was prepared in one step from ordinary [...] Read more.
An efficient reduction of double bonds conjugated with nitrile groups and acid or base sensitive furan rings with 2-phenylbenzimidazoline generated in situ has been successfully accomplished with high yields and excellent selectivity. The employed reducing agent was prepared in one step from ordinary chemicals. The other advantages of the presented method include mild and convenient reaction conditions, a benign and cost effective reagent, simple work-up and separation of the products. As this process does neither affect cyano and nitro groups nor furan rings, it is a valuable alternative when metal-catalyzed hydrogenations or borohydride reductions have failed. Full article
(This article belongs to the Section Organic Chemistry)
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451 KiB  
Article
Preparation of an Immunoaffinity Column with Amino-Silica Gel Microparticles and Its Application in Sample Cleanup for Aflatoxin Detection in Agri-Products
by Fei Ma, Ran Chen, Peiwu Li, Qi Zhang, Wen Zhang and Xiaofeng Hu
Molecules 2013, 18(2), 2222-2235; https://doi.org/10.3390/molecules18022222 - 11 Feb 2013
Cited by 41 | Viewed by 5982
Abstract
This study established an immunoaffinity column for selective extraction of aflatoxins in agri-products. Specifically, the immunoaffinity column was developed by covalently coupling monoclonal antibody 1C11 against aflatoxins to amino-silica gel microparticles and then packing these into a cartridge. The extraction conditions were thoroughly [...] Read more.
This study established an immunoaffinity column for selective extraction of aflatoxins in agri-products. Specifically, the immunoaffinity column was developed by covalently coupling monoclonal antibody 1C11 against aflatoxins to amino-silica gel microparticles and then packing these into a cartridge. The extraction conditions were thoroughly optimized in terms of loading, washing and eluting solutions. Under the optimal conditions, the immunoaffinity column had a capacity of 200 ng of aflatoxins. The detection limits (S/N = 3) for aflatoxin G1, B1, G2 and B2 were 0.03, 0.07, 0.05 and 0.09 μg·kg−1, and the corresponding quantification limits (S/N = 10) were 0.10, 0.25, 0.18 and 0.30 μg·kg−1, respectively. The recoveries of aflatoxins in samples were 90.1%–104.4% and RSDs were <4.4%. The developed method was further applied to the determination of aflatoxins in peanut, vegetable oil and tea samples, and the results indicated that peanut (26.9%), vegetable oils (28.0%) and tea (5.3%) samples were contaminated with aflatoxins, with levels ranging from 0.49 to 20.79 μg·kg−1. Full article
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285 KiB  
Article
New Spiral γ-Lactone Enantiomers from the Plant Endophytic Fungus Pestalotiopsis foedan
by Xiao-Long Yang and Zhuang-Zhuang Li
Molecules 2013, 18(2), 2236-2242; https://doi.org/10.3390/molecules18022236 - 11 Feb 2013
Cited by 13 | Viewed by 5061
Abstract
(−)-(4S, 8S)-Foedanolide (1a) and (+)-(4R, 8R)-foedanolide (1b), a pair of new spiro-γ-lactone enantiomers, were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis foedan by HPLC using a chiral [...] Read more.
(−)-(4S, 8S)-Foedanolide (1a) and (+)-(4R, 8R)-foedanolide (1b), a pair of new spiro-γ-lactone enantiomers, were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis foedan by HPLC using a chiral column, achieving over 7% ee. Their structures and absolute configurations were determined on the basis of extensive analysis of NMR spectra combined with computational methods via calculation of the electronic circular dichroism (ECD) and optical rotation (OR). Compounds 1a and 1b showed moderate activities against HeLa, A-549, U-251, HepG2 and MCF-7 tumor cell lines. Full article
(This article belongs to the Section Natural Products Chemistry)
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576 KiB  
Article
Growth of Fullerene Fragments Using the Diels-Alder Cycloaddition Reaction: First Step towards a C60 Synthesis by Dimerization
by Martha Mojica, Francisco Méndez and Julio A. Alonso
Molecules 2013, 18(2), 2243-2254; https://doi.org/10.3390/molecules18022243 - 13 Feb 2013
Cited by 6 | Viewed by 5367
Abstract
Density Functional Theory has been used to model the Diels-Alder reactions of the fullerene fragments triindenetriphenilene and pentacyclopentacorannulene with ethylene and 1,3-butadiene. The purpose is to prove the feasibility of using Diels-Alder cycloaddition reactions to grow fullerene fragments step by step, and to [...] Read more.
Density Functional Theory has been used to model the Diels-Alder reactions of the fullerene fragments triindenetriphenilene and pentacyclopentacorannulene with ethylene and 1,3-butadiene. The purpose is to prove the feasibility of using Diels-Alder cycloaddition reactions to grow fullerene fragments step by step, and to dimerize fullerene fragments, as a way to obtain C60. The dienophile character of the fullerene fragments is dominant, and the reaction of butadiene with pentacyclopentacorannulene is favored. Full article
(This article belongs to the Special Issue Diels-Alder Reaction)
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385 KiB  
Article
Characterization of Proanthocyanidins in Stems of Polygonum multiflorum Thunb as Strong Starch Hydrolase Inhibitors
by Hongyu Wang, Lixia Song, Shengbao Feng, Yuancai Liu, Gang Zuo, Fuli Lai, Guangyuan He, Mingjie Chen and Dejian Huang
Molecules 2013, 18(2), 2255-2265; https://doi.org/10.3390/molecules18022255 - 18 Feb 2013
Cited by 31 | Viewed by 7313
Abstract
Characterzation of polyphenolic compounds in the stems of P. multiflorum was conducted using HPLC, high resolution LC-MS and LC-MSn. Proanthocyanidins in particular were isolated in 4.8% yield using solvent extraction followed by Sephadex LH-20 fractionation. HPLC analysis using a diol column [...] Read more.
Characterzation of polyphenolic compounds in the stems of P. multiflorum was conducted using HPLC, high resolution LC-MS and LC-MSn. Proanthocyanidins in particular were isolated in 4.8% yield using solvent extraction followed by Sephadex LH-20 fractionation. HPLC analysis using a diol column revealed oligomers (from dimer to nonamer) as minor components, with (epi)catechin monomeric units predominating, and oligomers with higher degree of polymerization being dominant. Thiolysis treatment of the proanthocyanidins using mercaptoacetic acid produced thioether derivatives of (epi)catechin as the major product and a mean value of the degree of polymerization of 32.6 was estimated from the ratio of terminal and extension units of the (epi)catechin. The isolated proanthocyanidins were shown to strongly inhibit α-amylase with an acarbose equivalence (AE) value of 1,954.7 µmol AE/g and inhibit α-glucosidase with an AE value of 211.1 µmol AE/g. Full article
(This article belongs to the Section Natural Products Chemistry)
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493 KiB  
Article
Quenching of Tryptophan Fluorescence in the Presence of 2,4-DNP, 2,6-DNP, 2,4-DNA and DNOC and Their Mechanism of Toxicity
by Cristina-Amalia Dumitraş Huţanu, Marius Zaharia and Olga Pintilie
Molecules 2013, 18(2), 2266-2280; https://doi.org/10.3390/molecules18022266 - 18 Feb 2013
Cited by 9 | Viewed by 7843
Abstract
Although they are widely used as insecticides, acaricides and fungicides in the agriculture or as raw materials in the dye industry, dinitrophenols (DNPs) are extremely noxious, death cases having been registered. These compounds produce cataracts, lower leucocyte levels, disturb the general metabolism and [...] Read more.
Although they are widely used as insecticides, acaricides and fungicides in the agriculture or as raw materials in the dye industry, dinitrophenols (DNPs) are extremely noxious, death cases having been registered. These compounds produce cataracts, lower leucocyte levels, disturb the general metabolism and can cause cancer. It is also assumed that DNPs hinder the proton translocation through the mitochondrial inner membrane and therefore inhibit oxidative phosphorylation. Their fluorescence quenching properties can help understand and explain their toxicity. Fluorescence quenching of tryptophan was tested using different dinitrophenols such as 2,4-dinitrophenol (2,4-DNP), 4,6-dinitro-orthocresol (DNOC), 2-[(2,4-dinitrophenyl)amino]acetic acid (GlyDNP), 2-(1-methyl-heptyl)-4.6-dinitrophenyl crotonate (Karathan), 2-amino-5-[(1-((carboxymethyl)amino)-3-((2,4-dinitrophenyl)thio)-1-oxopropan-2-yl)amino]-5-oxopentanoic acid (SDN GSH), 2,4-dinitroanisole (2,4-DNA) and 2,4-dinitrobenzoic acid (2,4-DNB). 2,4-DNP and DNOC showed the highest tryptophan fluorescence quenching constant values, these being also the most toxic compounds. The electronic chemical potential value of the most stable complex of 2,4-DNP-with tryptophan is higher than the values of the electronic chemical potentials of complexes corresponding to the derivatives. Full article
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530 KiB  
Article
Enthalpy/Entropy Contributions to Conformational KIEs: Theoretical Predictions and Comparison with Experiment
by Aaron Fong, Matthew P. Meyer and Daniel J. O'Leary
Molecules 2013, 18(2), 2281-2296; https://doi.org/10.3390/molecules18022281 - 18 Feb 2013
Cited by 8 | Viewed by 6094
Abstract
Previous theoretical studies of Mislow’s doubly-bridged biphenyl ketone 1 and dihydrodimethylphenanthrene 2 have determined significant entropic contributions to their normal (1) and inverse (2) conformational kinetic isotope effects (CKIEs). To broaden our investigation, we have used density functional methods [...] Read more.
Previous theoretical studies of Mislow’s doubly-bridged biphenyl ketone 1 and dihydrodimethylphenanthrene 2 have determined significant entropic contributions to their normal (1) and inverse (2) conformational kinetic isotope effects (CKIEs). To broaden our investigation, we have used density functional methods to characterize the potential energy surfaces and vibrational frequencies for ground and transition structures of additional systems with measured CKIEs, including [2.2]-metaparacyclophane-d (3), 1,1'-binaphthyl (4), 2,2'-dibromo-[1,1'-biphenyl]-4,4'-dicarboxylic acid (5), and the 2-(N,N,N-trimethyl)-2'-(N,N-dimethyl)-diaminobiphenyl cation (6). We have also computed CKIEs in a number of systems whose experimental CKIEs are unknown. These include analogs of 1 in which the C=O groups have been replaced with CH2 (7), O (8), and S (9) atoms and ring-expanded variants of 2 containing CH2 (10), O (11), S (12), or C=O (13) groups. Vibrational entropy contributes to the CKIEs in all of these systems with the exception of cyclophane 3, whose isotope effect is predicted to be purely enthalpic in origin and whose Bigeleisen-Mayer ZPE term is equivalent to ΔΔ H. There is variable correspondence between these terms in the other molecules studied, thus identifying additional examples of systems in which the Bigeleisen-Mayer formalism does not correlate with ΔHS dissections. Full article
(This article belongs to the Collection Isotope Effects)
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364 KiB  
Article
Neglschisandrins E–F: Two New Lignans and Related Cytotoxic Lignans from Schisandra neglecta
by Min Chen, Xiumei Xu, Bing Xu, Panpan Yang, Zhihua Liao, Susan L. Morris-Natschke, Kuo-Hsiung Lee and Daofeng Chen
Molecules 2013, 18(2), 2297-2306; https://doi.org/10.3390/molecules18022297 - 19 Feb 2013
Cited by 17 | Viewed by 5827
Abstract
Phytochemical investigation of an ethanolic extract of stems of Schisandra neglecta led to the isolation and identification of two new dibenzocyclooctadiene lignans, designated neglschisandrins E (1) and F (2), and thirteen known lignans. All structures and stereochemistries were determined [...] Read more.
Phytochemical investigation of an ethanolic extract of stems of Schisandra neglecta led to the isolation and identification of two new dibenzocyclooctadiene lignans, designated neglschisandrins E (1) and F (2), and thirteen known lignans. All structures and stereochemistries were determined by spectroscopic methods, including 2D-NMR techniques. The isolates were evaluated for in vitro cytotoxic activity. Among them, compounds 26 exhibited moderate to weak cytotoxicity against the human colorectal carcinoma HCT-8 cell line with EC50 values of 7.33~19.8 μg/mL. In addition, compounds 24 also exhibited marginal cytotoxicity against the human lung carcinoma A549 cell line with EC50 values of 11.8~15.0 μg/mL. Full article
(This article belongs to the Section Natural Products Chemistry)
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237 KiB  
Article
Free Radical Scavenging Activity of Kielmeyera variabilis (Clusiaceae)
by Aline Coqueiro, Luis Octávio Regasini, Scheila Cristina Gutkoski Skrzek, Marcos Marçal Ferreira Queiroz, Dulce Helena Siqueira Silva and Vanderlan Da Silva Bolzani
Molecules 2013, 18(2), 2376-2385; https://doi.org/10.3390/molecules18022376 - 19 Feb 2013
Cited by 17 | Viewed by 5995
Abstract
As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH· (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS·+ [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl [...] Read more.
As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH· (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS·+ [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl acetate and n-butanol fractions of the leaves of K. variabilis displayed the strongest activity (IC50 of 3.5 ± 0.3 and 4.4 ± 0.2 μg mL−1 for DPPH· and 6.6 ± 0.4 and 3.1 ± 0.1 μg mL−1 for ABTS·+, respectively). Chromatographic fractionation of the most potent fractions led to identification of three flavonols with previously described antioxidant activity, quercitrin (1), quercetin-3-O-b-glucoside (3), and quercetin-3-O-b-galactoside (4), and of one biflavone, podocarpusflavone A (2). This is the first time that the presence of these flavonoids in Kielmeyera variabilis has been reported. Full article
(This article belongs to the Section Natural Products Chemistry)
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821 KiB  
Article
Synthesis and Crystal Structures of N-Substituted Pyrazolines
by Wan-Sin Loh, Ching Kheng Quah, Tze Shyang Chia, Hoong-Kun Fun, Majal Sapnakumari, Badiadka Narayana and Balladka Kunhanna Sarojini
Molecules 2013, 18(2), 2386-2396; https://doi.org/10.3390/molecules18022386 - 20 Feb 2013
Cited by 11 | Viewed by 6134
Abstract
Four pyrazole compounds, 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde (1), 5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (2), 1-[5-(4-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone (3) and 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]propan-1-one (4), have been prepared by condensing chalcones with hydrazine hydrate in the presence of aliphatic acids, [...] Read more.
Four pyrazole compounds, 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde (1), 5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (2), 1-[5-(4-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone (3) and 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]propan-1-one (4), have been prepared by condensing chalcones with hydrazine hydrate in the presence of aliphatic acids, namely formic acid, acetic acid and propionic acid. The structures were characterized by X-ray single crystal structure determination. The dihedral angles formed between the pyrazole and the fluoro-substituted rings are 4.64(7)° in 1, 5.3(4)° in 2 and 4.89(6)° in 3. In 4, the corresponding angles for molecules A and molecules B are 10.53(10)° and 9.78(10)°, respectively. Full article
(This article belongs to the Section Organic Chemistry)
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510 KiB  
Article
7-Methoxytacrine-Adamantylamine Heterodimers as Cholinesterase Inhibitors in Alzheimer’s Disease Treatment — Synthesis, Biological Evaluation and Molecular Modeling Studies
by Katarina Spilovska, Jan Korabecny, Jan Kral, Anna Horova, Kamil Musilek, Ondrej Soukup, Lucie Drtinova, Zuzana Gazova, Katarina Siposova and Kamil Kuca
Molecules 2013, 18(2), 2397-2418; https://doi.org/10.3390/molecules18022397 - 20 Feb 2013
Cited by 69 | Viewed by 9553
Abstract
A structural series of 7-MEOTA-adamantylamine thioureas was designed, synthesized and evaluated as inhibitors of human acetylcholinesterase (hAChE) and human butyrylcholinesterase (hBChE). The compounds were prepared based on the multi-target-directed ligand strategy with different linker lengths (n = 2–8) joining the well-known NMDA antagonist [...] Read more.
A structural series of 7-MEOTA-adamantylamine thioureas was designed, synthesized and evaluated as inhibitors of human acetylcholinesterase (hAChE) and human butyrylcholinesterase (hBChE). The compounds were prepared based on the multi-target-directed ligand strategy with different linker lengths (n = 2–8) joining the well-known NMDA antagonist adamantine and the hAChE inhibitor 7-methoxytacrine (7-MEOTA). Based on in silico studies, these inhibitors proved dual binding site character capable of simultaneous interaction with the peripheral anionic site (PAS) of hAChE and the catalytic active site (CAS). Clearly, these structural derivatives exhibited very good inhibitory activity towards hBChE resulting in more selective inhibitors of this enzyme. The most potent cholinesterase inhibitor was found to be thiourea analogue 14 (with an IC50 value of 0.47 µM for hAChE and an IC50 value of 0.11 µM for hBChE, respectively). Molecule 14 is a suitable novel lead compound for further evaluation proving that the strategy of dual binding site inhibitors might be a promising direction for development of novel AD drugs. Full article
(This article belongs to the Section Medicinal Chemistry)
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256 KiB  
Article
Sonolytic and Silent Polymerization of Methacrlyic Acid Butyl Ester Catalyzed by a New Onium Salt with bis-Active Sites in a Biphasic System — A Comparative Investigation
by Perumberkandgai A. Vivekanand, Maw-Ling Wang and Yu-Ming Hsieh
Molecules 2013, 18(2), 2419-2437; https://doi.org/10.3390/molecules18022419 - 21 Feb 2013
Cited by 12 | Viewed by 5686
Abstract
Currently, ingenious new analytical and process experimental techniques which are environmentally benign techniques, viz., ultrasound irradiation, have become immensely popular in promoting various reactions. In this work, a novel soluble multi-site phase transfer catalyst (PTC) viz., 1,4-bis-(propylmethyleneammounium chloride)benzene (BPMACB) was synthesized [...] Read more.
Currently, ingenious new analytical and process experimental techniques which are environmentally benign techniques, viz., ultrasound irradiation, have become immensely popular in promoting various reactions. In this work, a novel soluble multi-site phase transfer catalyst (PTC) viz., 1,4-bis-(propylmethyleneammounium chloride)benzene (BPMACB) was synthesized and its catalytic efficiency was assessed by observing the kinetics of sonolytic polymerization of methacrylic acid butyl ester (MABE) using potassium persulphate (PPS) as an initiator. The ultrasound–multi-site phase transfer catalysis (US-MPTC)-assisted polymerization reaction was compared with the silent (non-ultrasonic) polymerization reaction. The effects of the catalyst and various reaction parameters on the catalytic performance were in detail investigated by following the kinetics of polymerization of MABE in an ethyl acetate-water biphasic system. From the detailed kinetic investigation we propose a plausible mechanism. Further the kinetic results demonstrate clearly that ultrasound-assisted phase-transfer catalysis significantly increased the reaction rate when compared to silent reactions. Notably, this environmentally benign and cost-effective process has great potential to be applied in various polymer industries. Full article
(This article belongs to the Special Issue Phase Transfer Catalysis)
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310 KiB  
Article
The Tandem Ring Opening/Ring Closing Metathesis Route to Oxaspirocycles: An Approach to Phelligridin G
by Harold D. Cooper and Dennis L. Wright
Molecules 2013, 18(2), 2438-2448; https://doi.org/10.3390/molecules18022438 - 21 Feb 2013
Cited by 11 | Viewed by 5979
Abstract
Phelligridin G is an unusual natural product that contains an embedded spiro-fused furanone core. We have investigated two furan-based synthetic approaches towards the spirocyclic core structure of this natural product from readily available 2-phenylfurans. Although initial studies involving an oxidative cyclization were unsuccessful, [...] Read more.
Phelligridin G is an unusual natural product that contains an embedded spiro-fused furanone core. We have investigated two furan-based synthetic approaches towards the spirocyclic core structure of this natural product from readily available 2-phenylfurans. Although initial studies involving an oxidative cyclization were unsuccessful, we were ultimately able to access this key system through a sequential intermolecular furan Diels-Alder reaction followed by a metathesis-based reorganization. A related approach led to an expanded C ring to form spiro-fused pyran spirocycles. Full article
(This article belongs to the Special Issue Spiro Compounds)
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276 KiB  
Communication
Brazilin Inhibits Growth and Induces Apoptosis in Human Glioblastoma Cells
by Dae-Young Lee, Mi-Kyoung Lee, Geum-Soog Kim, Hyung-Jun Noh and Min-Ho Lee
Molecules 2013, 18(2), 2449-2457; https://doi.org/10.3390/molecules18022449 - 21 Feb 2013
Cited by 52 | Viewed by 6515
Abstract
Brazilin, isolated from the methanol extract of the heart wood of Caesalpinia sappan, sensitizes cancer cells to apoptosis. Glioblastoma multiforme (GBM), which accounts for most cases of central nervous system malignancy, has a very poor prognosis and lacks effective therapeutic interventions. We, [...] Read more.
Brazilin, isolated from the methanol extract of the heart wood of Caesalpinia sappan, sensitizes cancer cells to apoptosis. Glioblastoma multiforme (GBM), which accounts for most cases of central nervous system malignancy, has a very poor prognosis and lacks effective therapeutic interventions. We, therefore, investigated the effects of different concentrations of and different periods of exposure to brazilin on cell proliferation and apoptosis in the glioma U87 cell line. Cell proliferation was investigated by MTT assays and growth curve analysis, apoptosis was assessed by FACS analysis and western blot studies. Brazilin showed dose-dependent inhibition of cell proliferation and induction of apoptosis in glioma cells. It also increased the ratio of cleaved poly-(ADP)-ribose polymerase and decreased the expression of caspase-3 and caspase-7. Full article
(This article belongs to the Section Medicinal Chemistry)
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Review

Jump to: Editorial, Research

757 KiB  
Review
Case Studies of the Synthesis of Bioactive Cyclodepsipeptide Natural Products
by Sara C. Stolze and Markus Kaiser
Molecules 2013, 18(2), 1337-1367; https://doi.org/10.3390/molecules18021337 - 24 Jan 2013
Cited by 25 | Viewed by 6699
Abstract
Cyclodepsipeptide natural products often display intriguing biological activities that along with their complex molecular scaffolds, makes them interesting targets for chemical synthesis. Although cyclodepsipeptides feature highly diverse chemical structures, their synthesis is often associated with similar synthetic challenges such as the establishment of [...] Read more.
Cyclodepsipeptide natural products often display intriguing biological activities that along with their complex molecular scaffolds, makes them interesting targets for chemical synthesis. Although cyclodepsipeptides feature highly diverse chemical structures, their synthesis is often associated with similar synthetic challenges such as the establishment of a suitable macrocyclization methodology. This review therefore compiles case studies of synthetic approaches to different bioactive cyclodepsipeptide natural products, thereby illustrating obstacles of cyclodepsipeptide synthesis as well as their overcomings. Full article
(This article belongs to the Special Issue Chemical Protein and Peptide Synthesis)
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640 KiB  
Review
Antioxidants Improve the Phenotypes of Dilated Cardiomyopathy and Muscle Fatigue in Mitochondrial Superoxide Dismutase-Deficient Mice
by Hirofumi Koyama, Hidetoshi Nojiri, Satoru Kawakami, Tadahiro Sunagawa, Takuji Shirasawa and Takahiko Shimizu
Molecules 2013, 18(2), 1383-1393; https://doi.org/10.3390/molecules18021383 - 24 Jan 2013
Cited by 34 | Viewed by 6764
Abstract
Redox imbalance elevates the reactive oxygen species (ROS) level in cells and promotes age-related diseases. Superoxide dismutases (SODs) are antioxidative enzymes that catalyze the degradation of ROS. There are three SOD isoforms: SOD1/CuZn-SOD, SOD2/Mn-SOD, and SOD3/EC-SOD. SOD2, which is localized in the mitochondria, [...] Read more.
Redox imbalance elevates the reactive oxygen species (ROS) level in cells and promotes age-related diseases. Superoxide dismutases (SODs) are antioxidative enzymes that catalyze the degradation of ROS. There are three SOD isoforms: SOD1/CuZn-SOD, SOD2/Mn-SOD, and SOD3/EC-SOD. SOD2, which is localized in the mitochondria, is an essential enzyme required for mouse survival, and systemic knockout causes neonatal lethality in mice. To investigate the physiological function of SOD2 in adult mice, we generated a conditional Sod2 knockout mouse using a Cre-loxP system. When Sod2 was specifically deleted in the heart and muscle, all mice exhibited dilated cardiomyopathy (DCM) and died by six months of age. On the other hand, when Sod2 was specifically deleted in the skeletal muscle, mice showed severe exercise disturbance without morphological abnormalities. These provide useful model of DCM and muscle fatigue. In this review, we summarize the impact of antioxidants, which were able to regulate mitochondrial superoxide generation and improve the phenotypes of the DCM and the muscle fatigue in mice. Full article
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199 KiB  
Review
Chemical Genetics of Acetyl-CoA Carboxylases
by Xuyu Zu, Jing Zhong, Dixian Luo, Jingjing Tan, Qinghai Zhang, Ying Wu, Jianghua Liu, Renxian Cao, Gebo Wen and Deliang Cao
Molecules 2013, 18(2), 1704-1719; https://doi.org/10.3390/molecules18021704 - 28 Jan 2013
Cited by 38 | Viewed by 14938
Abstract
Chemical genetic studies on acetyl-CoA carboxylases (ACCs), rate-limiting enzymes in long chain fatty acid biosynthesis, have greatly advanced the understanding of their biochemistry and molecular biology and promoted the use of ACCs as targets for herbicides in agriculture and for development of drugs [...] Read more.
Chemical genetic studies on acetyl-CoA carboxylases (ACCs), rate-limiting enzymes in long chain fatty acid biosynthesis, have greatly advanced the understanding of their biochemistry and molecular biology and promoted the use of ACCs as targets for herbicides in agriculture and for development of drugs for diabetes, obesity and cancers. In mammals, ACCs have both biotin carboxylase (BC) and carboxyltransferase (CT) activity, catalyzing carboxylation of acetyl-CoA to malonyl-CoA. Several classes of small chemicals modulate ACC activity, including cellular metabolites, natural compounds, and chemically synthesized products. This article reviews chemical genetic studies of ACCs and the use of ACCs for targeted therapy of cancers. Full article
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427 KiB  
Review
Pharmacological Actions of Multi-Target-Directed Evodiamine
by Hui Yu, Hongwei Jin, Wuzhuang Gong, Zhanli Wang and Huaping Liang
Molecules 2013, 18(2), 1826-1843; https://doi.org/10.3390/molecules18021826 - 31 Jan 2013
Cited by 149 | Viewed by 8272
Abstract
Evodiamine, a naturally occurring indole alkaloid, is one of the main bioactive ingredients of Evodiae fructus. With respect to the pharmacological actions of evodiamine, more attention has been paid to beneficial effects in insults involving cancer, obesity, nociception, inflammation, cardiovascular diseases, Alzheimer's [...] Read more.
Evodiamine, a naturally occurring indole alkaloid, is one of the main bioactive ingredients of Evodiae fructus. With respect to the pharmacological actions of evodiamine, more attention has been paid to beneficial effects in insults involving cancer, obesity, nociception, inflammation, cardiovascular diseases, Alzheimer's disease, infectious diseases and themoregulative effects. Evodiamine has evolved a superior ability to bind various proteins, so we also argue that it is good starting point for multi-target drugs. This review is primarily addressed to the description of the recent advances in the biological activity studies of evodiamine, with a focus on pharmacological mechanism. The present review also includes the pharmacokinetics and the detailed exploration of target-binding properties of evodiamine in an attempt to provide a direction for further multi-target drug design. Full article
(This article belongs to the Section Natural Products Chemistry)
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1038 KiB  
Review
3-Substituted Prolines: From Synthesis to Structural Applications, from Peptides to Foldamers
by Céline Mothes, Cécile Caumes, Alexandre Guez, Héloïse Boullet, Thomas Gendrineau, Sylvain Darses, Nicolas Delsuc, Roba Moumné, Benoit Oswald, Olivier Lequin and Philippe Karoyan
Molecules 2013, 18(2), 2307-2327; https://doi.org/10.3390/molecules18022307 - 19 Feb 2013
Cited by 38 | Viewed by 11147
Abstract
Among the twenty natural proteinogenic amino acids, proline is unique as its secondary amine forms a tertiary amide when incorporated into biopolymers, thus preventing hydrogen bond formation. Despite the lack of hydrogen bonds and thanks to conformational restriction of flexibility linked to the [...] Read more.
Among the twenty natural proteinogenic amino acids, proline is unique as its secondary amine forms a tertiary amide when incorporated into biopolymers, thus preventing hydrogen bond formation. Despite the lack of hydrogen bonds and thanks to conformational restriction of flexibility linked to the pyrrolidine ring, proline is able to stabilize peptide secondary structures such as b-turns or polyproline helices. These unique conformational properties have aroused a great interest in the development of proline analogues. Among them, proline chimeras are tools combining the proline restriction of flexibility together with the information brought by natural amino acids side chains. This review will focus on the chemical syntheses of 3-substituted proline chimeras of potential use for peptide syntheses and as potential use as tools for SAR studies of biologically active peptides and the development of secondary structure mimetics. Their influence on peptide structure will be briefly described. Full article
(This article belongs to the Special Issue Chemical Protein and Peptide Synthesis)
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600 KiB  
Review
Techniques for Analysis of Plant Phenolic Compounds
by Ali Khoddami, Meredith A. Wilkes and Thomas H. Roberts
Molecules 2013, 18(2), 2328-2375; https://doi.org/10.3390/molecules18022328 - 19 Feb 2013
Cited by 866 | Viewed by 61919
Abstract
Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules [...] Read more.
Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules have occurred over the last 25 years. Organic solvent extraction is the main method used to extract phenolics. Chemical procedures are used to detect the presence of total phenolics, while spectrophotometric and chromatographic techniques are utilized to identify and quantify individual phenolic compounds. This review addresses the application of different methodologies utilized in the analysis of phenolic compounds in plant-based products, including recent technical developments in the quantification of phenolics. Full article
(This article belongs to the Special Issue Methods in Polyphenol Analysis)
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