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Molecules, Volume 18, Issue 1 (January 2013) – 84 articles , Pages 1-1336

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276 KiB  
Article
Chemical Constituents of Caesalpinia decapetala (Roth) Alston
by Xiao-Hua Wei, Sheng-Jie Yang, Na Liang, De-Yu Hu, Lin-Hong Jin, Wei Xue and Song Yang
Molecules 2013, 18(1), 1325-1336; https://doi.org/10.3390/molecules18011325 - 22 Jan 2013
Cited by 80 | Viewed by 8613
Abstract
The current study targets the chemical constituents of Caesalpinia decapetala (Roth) Alston and investigates the bioactivities of the isolated compounds. Fourteen known compounds were isolated using column chromatography, and structural identification was performed by physical and spectral analyses. The biological activities of the [...] Read more.
The current study targets the chemical constituents of Caesalpinia decapetala (Roth) Alston and investigates the bioactivities of the isolated compounds. Fourteen known compounds were isolated using column chromatography, and structural identification was performed by physical and spectral analyses. The biological activities of the compounds were also evaluated by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 2,2-diphenlyl-1-picrylhydrazyl (DPPH) assays. Emodin (6), baicalein (9), and apigenin (12) displayed antitumor activities against the MGC-803 cell line, while quercetin (2), rutin (5), baicalein (9), and epicatechin (13) showed stronger DPPH scavenging activities compared with ascorbic acid. Andrographolide (1), quercetin (2), bergenin (4), rutin (5), emodin (6), betulin (7), baicalein (9), polydatin (10), salicin (11), and apigenin (12), were obtained from C. decapetala (Roth) Alston for the first time. Full article
(This article belongs to the Section Natural Products Chemistry)
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302 KiB  
Article
Photochemical Synthesis and Properties of 1,6- and 1,8-Naphthalenophanes
by Pablo Wessig and Annika Matthes
Molecules 2013, 18(1), 1314-1324; https://doi.org/10.3390/molecules18011314 - 21 Jan 2013
Cited by 9 | Viewed by 4541
Abstract
Various 1,6- and 1,8-naphthalenophanes were synthesized by using the Photo-Dehydro-Diels-Alder (PDDA) reaction of bis-ynones. These compounds are easily accessible from w-(3-iodophenyl)carboxylic acids in three steps. The obtained naphthalenophanes are axially chiral and the activation barrier for the atropisomerization could be determined in some [...] Read more.
Various 1,6- and 1,8-naphthalenophanes were synthesized by using the Photo-Dehydro-Diels-Alder (PDDA) reaction of bis-ynones. These compounds are easily accessible from w-(3-iodophenyl)carboxylic acids in three steps. The obtained naphthalenophanes are axially chiral and the activation barrier for the atropisomerization could be determined in some cases by means of dynamic NMR (DNMR) and/or dynamic HPLC (DHPLC) experiments. Full article
(This article belongs to the Special Issue New Trends in Photochemistry)
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989 KiB  
Review
Chemistry and Applications of Polysaccharide Solutions in Strong Electrolytes/Dipolar Aprotic Solvents: An Overview
by Omar A. El Seoud, Haq Nawaz and Elizabeth P. G. Arêas
Molecules 2013, 18(1), 1270-1313; https://doi.org/10.3390/molecules18011270 - 21 Jan 2013
Cited by 53 | Viewed by 9563
Abstract
Biopolymers and their derivatives are being actively investigated as substitutes for petroleum-based polymers. This has generated an intense interest in investigating new solvents, in particular for cellulose, chitin/chitosan, and starch. This overview focuses on recent advances in the dissolution and derivatization of these [...] Read more.
Biopolymers and their derivatives are being actively investigated as substitutes for petroleum-based polymers. This has generated an intense interest in investigating new solvents, in particular for cellulose, chitin/chitosan, and starch. This overview focuses on recent advances in the dissolution and derivatization of these polysaccharides in solutions of strong electrolytes in dipolar aprotic solvents. A brief description of the molecular structures of these biopolymers is given, with emphases on the properties that are relevant to derivatization, namely crystallinity and accessibility. The mechanism of cellulose dissolution is then discussed, followed by a description of the strategies employed for the synthesis of cellulose derivatives (carboxylic acid esters, and ethers) under homogeneous reaction conditions. The same sequence of presentation has been followed for chitin/chitosan and starch. Future perspectives for this subject are summarized, in particular with regard to compliance with the principles of green chemistry. Full article
(This article belongs to the Special Issue Advances in Carbohydrate Chemistry 2012)
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280 KiB  
Article
A New Triterpenoid from Teucrium viscidum
by Xincai Hao, Jinwen Zhang, Guangxin Xia, Yongbo Xue, Zengwei Luo, Yanyan Si, Guangmin Yao and Yonghui Zhang
Molecules 2013, 18(1), 1262-1269; https://doi.org/10.3390/molecules18011262 - 21 Jan 2013
Cited by 14 | Viewed by 6170
Abstract
A new ursane-type triterpenoid, 3β-hydroxy-urs-30-p-Z-hydroxycinnamoyloxy-12-en-28-oic-acid (1), together with three known triterpenoids, 3β-hydroxy-urs-30-p-E-hydroxycinnamoyloxy-12-en-28-oic-acid (2), 2α,3β,19α-trihydroxy-urs-12-en-28-oic-acid (3), and ursolic acid ( [...] Read more.
A new ursane-type triterpenoid, 3β-hydroxy-urs-30-p-Z-hydroxycinnamoyloxy-12-en-28-oic-acid (1), together with three known triterpenoids, 3β-hydroxy-urs-30-p-E-hydroxycinnamoyloxy-12-en-28-oic-acid (2), 2α,3β,19α-trihydroxy-urs-12-en-28-oic-acid (3), and ursolic acid (4), four known lignans, pinoresinol (5), 9α-hydroxypinoresinol (6), (+)-medioresinol (7), and (+)-kobusin (8), and two steroids, β-sitosterol (9), and daucosterol (10), were isolated from the whole parts of Teucrium viscidum. Their structures were established by a combination of spectroscopic data analysis, besides comparison with literature data. Compounds 14 were evaluated for their inhibitory activities against 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1). Full article
(This article belongs to the Special Issue Triterpenes and Triterpenoids 2013)
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235 KiB  
Article
A New Phenolic Glycoside from Chamaecyparis obtusa var. breviramea f. crippsii
by Yu-Mei Zhang, Jian Xu, Lin Xiao, Guang-Zhi Zeng, Zhang-Hua Sun and Ning-Hua Tan
Molecules 2013, 18(1), 1255-1261; https://doi.org/10.3390/molecules18011255 - 18 Jan 2013
Cited by 11 | Viewed by 5599
Abstract
A new phenolic glycoside, 3-methoxyphenol 1-O-α-L-rhamnopyranosyl-(1→6)- O-β-D-glucopyranoside (1), was isolated from the 90% acetone extract of the branches and leaves of Chamaecyparis obtusa var. breviramea f. crippsii along with another 10 known phenolics 2 [...] Read more.
A new phenolic glycoside, 3-methoxyphenol 1-O-α-L-rhamnopyranosyl-(1→6)- O-β-D-glucopyranoside (1), was isolated from the 90% acetone extract of the branches and leaves of Chamaecyparis obtusa var. breviramea f. crippsii along with another 10 known phenolics 211. Their structures were determined mainly by means of MS, 1D- and 2D-NMR data. Cytotoxicities of compounds 3 and 511 were tested on BGC-823, Hela and A549 cancer cell lines, the results showed that compound 8 was bioactive and its IC50 values were 6.9, 29.7 and 52.9 μM, respectively. Full article
(This article belongs to the Section Natural Products Chemistry)
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266 KiB  
Review
A Review on Anti-Inflammatory Activity of Monoterpenes
by Rita De Cássia da Silveira e Sá, Luciana Nalone Andrade and Damião Pergentino De Sousa
Molecules 2013, 18(1), 1227-1254; https://doi.org/10.3390/molecules18011227 - 18 Jan 2013
Cited by 424 | Viewed by 31550
Abstract
Faced with the need to find new anti-inflammatory agents, great effort has been expended on the development of drugs for the treatment of inflammation. This disorder reduces the quality of life and overall average productivity, causing huge financial losses. In this review the [...] Read more.
Faced with the need to find new anti-inflammatory agents, great effort has been expended on the development of drugs for the treatment of inflammation. This disorder reduces the quality of life and overall average productivity, causing huge financial losses. In this review the anti-inflammatory activity of 32 bioactive monoterpenes found in essential oils is discussed. The data demonstrate the pharmacological potential of this group of natural chemicals to act as anti-inflammatory drugs. Full article
(This article belongs to the Section Natural Products Chemistry)
988 KiB  
Article
Protective Effect of Ginsenoside Rb1 Against Lung Injury Induced by Intestinal Ischemia-Reperfusion in Rats
by Jin Wang, Lifen Qiao, Shusheng Li and Guangtian Yang
Molecules 2013, 18(1), 1214-1226; https://doi.org/10.3390/molecules18011214 - 17 Jan 2013
Cited by 49 | Viewed by 5992
Abstract
Intestinal ischemia-reperfusion (I/R) is a critical event in the pathogenesis of multiple organ dysfunction syndromes (MODS). The lungs are some of the most vulnerable organs that are impacted by intestinal I/R. The aim of this study is to investigate whether ginsenoside Rb1 can [...] Read more.
Intestinal ischemia-reperfusion (I/R) is a critical event in the pathogenesis of multiple organ dysfunction syndromes (MODS). The lungs are some of the most vulnerable organs that are impacted by intestinal I/R. The aim of this study is to investigate whether ginsenoside Rb1 can ameliorate remote lung injury induced by intestinal I/R. Adult male Wistar rats were randomly divided into four groups: (1) a control, sham-operated group (sham group); (2) an intestinal I/R group subjected to 1 h intestinal ischemia and 2 h reperfusion (I/R group); (3) a group treated with 20 mg/kg ginsenoside Rb1 before reperfusion (Rb1-20 group); and (4) a group treated with 40 mg/kg ginsenoside Rb1 before reperfusion (Rb1-40 group). Intestinal and lung histology was observed. The malondialdehyde (MDA) levels in intestinal tissues were measured. Myeloperoxidase (MPO), TNF-α, MDA levels, wet/dry weight ratio and immunohistochemical expression of intracellular adhesion molecule-1 (ICAM-1) in lung tissues were assayed. In addition, a western blot of lung NF-kB was performed. Results indicated that intestinal I/R induced intestinal and lung injury, which was characterized by increase of MDA levels and pathological scores in intestinal tissues and MPO, TNF-α , MDA levels, wet/dry weight ratio and ICAM-1, NF-kB expression in the lung tissues. Ginsenoside Rb1 (20, 40 mg/kg) ameliorated intestinal and lung injury, decreased MPO, TNF-α, MDA levels, wet/dry weight ratio, ICAM-1 and NF-kB expression in lung tissues. In conclusion, ginsenoside Rb1 ameliorated the lung injuries by decreasing the NF-kB activation-induced inflammatory response. Full article
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472 KiB  
Review
Suzuki-Miyaura Cross-Coupling in Acylation Reactions, Scope and Recent Developments
by Marco Blangetti, Heléna Rosso, Cristina Prandi, Annamaria Deagostino and Paolo Venturello
Molecules 2013, 18(1), 1188-1213; https://doi.org/10.3390/molecules18011188 - 17 Jan 2013
Cited by 130 | Viewed by 12245
Abstract
Since the first report and due to its handiness and wide scope, the Suzuki-Miyaura (SM) cross coupling reaction has become a routine methodology in many laboratories worldwide. With respect to other common transition metal catalyzed cross couplings, the SM reaction has been so [...] Read more.
Since the first report and due to its handiness and wide scope, the Suzuki-Miyaura (SM) cross coupling reaction has become a routine methodology in many laboratories worldwide. With respect to other common transition metal catalyzed cross couplings, the SM reaction has been so far less exploited as a tool to introduce an acyl function into a specific substrate. In this review, the various approaches found in the literature will be considered, starting from the direct SM acylative coupling to the recent developments of cross coupling between boronates and acyl chlorides or anhydrides. Special attention will be dedicated to the use of masked acyl boronates, alkoxy styryl and alkoxy dienyl boronates as coupling partners. A final section will be then focused on the acyl SM reaction as key synthetic step in the framework of natural products synthesis. Full article
(This article belongs to the Special Issue Suzuki Reaction)
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220 KiB  
Article
Two Cerebrosides Isolated from the Seeds of Sterculia lychnophora and Their Neuroprotective Effect
by Ru-Feng Wang, Xiu-Wen Wu and Di Geng
Molecules 2013, 18(1), 1181-1187; https://doi.org/10.3390/molecules18011181 - 17 Jan 2013
Cited by 21 | Viewed by 5793
Abstract
Two cerebrosides named 1-O-b-D-glucopyranosyl-(2S,3R,4E,8Z)-2-[(2-hydroxyoctadecanoyl)amido]-4,8-octadecadiene-1,3-diol (1) and soya-cerebroside I (2) were isolated from the seeds of Sterculia lychnophora for the first time. Their structures were completely characterized by [...] Read more.
Two cerebrosides named 1-O-b-D-glucopyranosyl-(2S,3R,4E,8Z)-2-[(2-hydroxyoctadecanoyl)amido]-4,8-octadecadiene-1,3-diol (1) and soya-cerebroside I (2) were isolated from the seeds of Sterculia lychnophora for the first time. Their structures were completely characterized by spectroscopic methods including IR, MS and NMR. Compound 1 exhibited moderate neuroprotective effect against SH-SY5Y cell damage induced by hydrogen peroxide. Full article
(This article belongs to the Section Natural Products Chemistry)
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262 KiB  
Article
Diastereoselective Synthesis of 5-Hydroxy-8-methoxy-1-oxaspiro[5,5]undeca-7,10-diene-9-one
by Guy L. Plourde and Thomas W. Scully
Molecules 2013, 18(1), 1174-1180; https://doi.org/10.3390/molecules18011174 - 17 Jan 2013
Cited by 1 | Viewed by 4736
Abstract
A short five steps synthesis of the title compound from vanillin is described. The racemic spiroether 7 was obtained in 61% yield and in >99% diastereomeric excess (by 1H-NMR) from the corresponding phenolic derivative 3 by oxidation with lead (IV) acetate. Full article
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269 KiB  
Article
A Facile Synthesis of Fully Protected meso-Diaminopimelic Acid (DAP) and Its Application to the Preparation of Lipophilic N-Acyl iE-DAP
by Yukako Saito, Yuichi Yoshimura, Hideaki Wakamatsu and Hiroki Takahata
Molecules 2013, 18(1), 1162-1173; https://doi.org/10.3390/molecules18011162 - 16 Jan 2013
Cited by 13 | Viewed by 6682
Abstract
Synthesis of beneficial protected meso-DAP 9 by cross metathesis of the Garner aldehyde-derived vinyl glycine 1b with protected allyl glycine 2 in the presence of Grubbs second-generation catalyst was performed. Preparation of lipophilic N-acyl iE-DAP as potent agonists of NOD 1-mediated [...] Read more.
Synthesis of beneficial protected meso-DAP 9 by cross metathesis of the Garner aldehyde-derived vinyl glycine 1b with protected allyl glycine 2 in the presence of Grubbs second-generation catalyst was performed. Preparation of lipophilic N-acyl iE-DAP as potent agonists of NOD 1-mediated immune response from 9 is described. Full article
(This article belongs to the Special Issue Chemical Protein and Peptide Synthesis)
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280 KiB  
Article
Bioassay-Guided Isolation of DPP-4 Inhibitory Fractions from Extracts of Submerged Cultured of Inonotus obliquus
by Yan Geng, Zhen-Ming Lu, Wei Huang, Hong-Yu Xu, Jin-Song Shi and Zheng-Hong Xu
Molecules 2013, 18(1), 1150-1161; https://doi.org/10.3390/molecules18011150 - 16 Jan 2013
Cited by 31 | Viewed by 7154
Abstract
Inonotus obliquus is a medicinal mushroom used in Russian and Eastern European folk medicine for the treatment of gastrointestinal cancer, cardiovascular disease and diabetes. Previous studies in our laboratory have demonstrated that the mycelium powders of I. obliquus possess significant antihyperglycemic effects in [...] Read more.
Inonotus obliquus is a medicinal mushroom used in Russian and Eastern European folk medicine for the treatment of gastrointestinal cancer, cardiovascular disease and diabetes. Previous studies in our laboratory have demonstrated that the mycelium powders of I. obliquus possess significant antihyperglycemic effects in a mouse model of diabetic disease induced by alloxan. However, the active ingredients of mycelium powders responsible for the diabetes activity have not been identified. This study aims to identify the active ingredients of I. obliquus mycelium powders by a bioassay-guided fractionation approach and explore the mechanism of action of these active ingredients by using a well-established DPP-4 (an important enzyme as a new therapeutic target for diabetes) inhibitory assay model. The results showed the chloroform extract of mycelium was potential inhibitory against DPP-4. Bioactivity guided fractionation led to the identification of 19 compounds using UPLC-Q-TOF-MS. Molecular docking between the compounds and DPP-4 revealed that compounds 5, 8, 9, 14, 15 may be the active components responsible for the DPP-4 inhibitory activity. Full article
(This article belongs to the Section Natural Products Chemistry)
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470 KiB  
Article
Improvement of the Enzyme Performance of Trypsin via Adsorption in Mesoporous Silica SBA-15: Hydrolysis of BAPNA
by Shanshan Li, Zhuofu Wu, Ming Lu, Zhi Wang and Zhengqiang Li
Molecules 2013, 18(1), 1138-1149; https://doi.org/10.3390/molecules18011138 - 16 Jan 2013
Cited by 20 | Viewed by 8597
Abstract
The enzymatic performance of trypsin in hydrolysis of N-α-benzoyl-DL-arginine-4-nitroanilide (BAPNA) was improved by adsorption on Santa Barbara Amorphous (SBA)-15 mesoporous silica. The optimal immobilization conditions were screened and the properties of immobilized enzyme have also been studied. Under the optimal conditions, the [...] Read more.
The enzymatic performance of trypsin in hydrolysis of N-α-benzoyl-DL-arginine-4-nitroanilide (BAPNA) was improved by adsorption on Santa Barbara Amorphous (SBA)-15 mesoporous silica. The optimal immobilization conditions were screened and the properties of immobilized enzyme have also been studied. Under the optimal conditions, the immobilized trypsin displays maximum specific activity (49.8 μmol/min/g). The results also indicate that the immobilized trypsin exhibits better storage stability. Full article
(This article belongs to the Section Medicinal Chemistry)
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199 KiB  
Article
Antioxidant and Antimicrobial Activities of 7-Hydroxy-calamenene-Rich Essential Oils from Croton cajucara Benth.
by Mariana M. B. Azevedo, Francisco C. M. Chaves, Catia A. Almeida, Humberto R. Bizzo, Rafael S. Duarte, Galba M. Campos-Takaki, Celuta S. Alviano and Daniela S. Alviano
Molecules 2013, 18(1), 1128-1137; https://doi.org/10.3390/molecules18011128 - 16 Jan 2013
Cited by 39 | Viewed by 7061
Abstract
Croton cajucara is a shrub native to the Amazon region locally known as “sacaca”. Two morphotypes are known: white and red “sacaca”. The essential oils (EO) obtained by hydrodistillation from leaves of the red morphotype were, in general, rich in 7-hydroxycalamenene (28.4%–37.5%). The [...] Read more.
Croton cajucara is a shrub native to the Amazon region locally known as “sacaca”. Two morphotypes are known: white and red “sacaca”. The essential oils (EO) obtained by hydrodistillation from leaves of the red morphotype were, in general, rich in 7-hydroxycalamenene (28.4%–37.5%). The effectiveness of these EO regarding the antimicrobial activity against pathogenic microorganisms was initially investigated by the drop test method, showing significant inhibition zones. Among the microorganisms tested, the essential oils rich in 7-hydroxycalamenene were more effective against methicillin resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Mycobacterium tuberculosis, M. smegmatis, Mucor circinelloides and Rhizopus oryzae. The minimum inhibitory concentrations (MIC) of the oils were determined using the broth dilution assay. It was possible to observe that 7-hydroxycalamenene-rich oils presented high antimicrobial activity, with MIC of 4.76 × 10−3 μg/mL for MRSA, 4.88 μg/mL for M. tuberculosis, 39.06 μg/mL for M. smegmatis, and 0.152 μg/mL for R. oryzae and 3.63 × 10−8 μg/mL for M. circinelloides. The antioxidant activity of this EO suggests that 7-hydroxycalamenene provides more antioxidant activity according with EC50 less than 63.59 μg/mL. Considering the bioactive potential of EOs and 7-hydroxycalamenene could be of great interest for development of antimicrobials for therapeutic use in treatment of bacterial and fungal infections in humans and/or veterinary practice. Full article
(This article belongs to the Special Issue Antioxidants 2012)
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165 KiB  
Communication
Ligand Binding Affinities of Arctigenin and Its Demethylated Metabolites to Estrogen Receptor Alpha
by Jong-Sik Jin, Jong-Hyun Lee and Masao Hattori
Molecules 2013, 18(1), 1122-1127; https://doi.org/10.3390/molecules18011122 - 16 Jan 2013
Cited by 13 | Viewed by 5253
Abstract
Phytoestrogens are defined as plant-derived compounds with estrogen-like activities according to their chemical structures and activities. Plant lignans are generally categorized as phytoestrogens. It was reported that (−)-arctigenin, the aglycone of arctiin, was demethylated to (−)-dihydroxyenterolactone (DHENL) by Eubacterium (E.) sp. ARC-2. Through [...] Read more.
Phytoestrogens are defined as plant-derived compounds with estrogen-like activities according to their chemical structures and activities. Plant lignans are generally categorized as phytoestrogens. It was reported that (−)-arctigenin, the aglycone of arctiin, was demethylated to (−)-dihydroxyenterolactone (DHENL) by Eubacterium (E.) sp. ARC-2. Through stepwise demethylation, E. sp. ARC-2 produced six intermediates, three mono-desmethylarctigenins and three di-desmethylarctigenins. In the present study, ligand binding affinities of (−)-arctigenin and its seven metabolites, including DHENL, were investigated for an estrogen receptor alpha, and found that demethylated metabolites had stronger binding affinities than (−)-arctigenin using a ligand binding screen assay method. The IC50 value of (2R,3R)-2-(4-hydroxy-3-methoxybenzyl)-3-(3,4-dihydroxybenzyl)-butyrolactone was 7.9 × 10−4 M. Full article
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371 KiB  
Article
Solid Phase versus Solution Phase Synthesis of Heterocyclic Macrocycles
by Seong Jong Kim and Shelli R. McAlpine
Molecules 2013, 18(1), 1111-1121; https://doi.org/10.3390/molecules18011111 - 16 Jan 2013
Cited by 16 | Viewed by 7629
Abstract
Comparing a solution phase route to a solid phase route in the synthesis of the cytotoxic natural product urukthapelstatin A (Ustat A) confirmed that a solid phase method is superior. The solution phase approach was tedious and involved cyclization of a ridged heterocyclic [...] Read more.
Comparing a solution phase route to a solid phase route in the synthesis of the cytotoxic natural product urukthapelstatin A (Ustat A) confirmed that a solid phase method is superior. The solution phase approach was tedious and involved cyclization of a ridged heterocyclic precursor, while solid phase allowed the rapid generation of a flexible linear peptide. Cyclization of the linear peptide was facile and subsequent generation of three oxazoles located within the structure of Ustat A proved relatively straightforward. Given the ease with which the oxazole Ustat A precursor is formed via our solid phase approach, this route is amenable to rapid analog synthesis. Full article
(This article belongs to the Special Issue Chemical Protein and Peptide Synthesis)
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312 KiB  
Article
Optimization of Ultrasonic Assisted Extraction of Antioxidants from Black Soybean (Glycine max var) Sprouts Using Response Surface Methodology
by Jixiang Lai, Can Xin, Ya Zhao, Bing Feng, Congfen He, Yinmao Dong, Yun Fang and Shaomin Wei
Molecules 2013, 18(1), 1101-1110; https://doi.org/10.3390/molecules18011101 - 16 Jan 2013
Cited by 44 | Viewed by 6348
Abstract
Response surface methodology (RSM) using a central composite design (CCD) was employed to optimize the conditions for extraction of antioxidants from black soybean (Glycine max var) sprouts. Three influencing factors: liquid-solid ratio, period of ultrasonic assisted extraction and extraction temperature were investigated [...] Read more.
Response surface methodology (RSM) using a central composite design (CCD) was employed to optimize the conditions for extraction of antioxidants from black soybean (Glycine max var) sprouts. Three influencing factors: liquid-solid ratio, period of ultrasonic assisted extraction and extraction temperature were investigated in the ultrasonic aqueous extraction. Then Response Surface Methodology (RSM) was applied to optimize the extraction process focused on DPPH radical-scavenging capacity of the antioxidants with respect to the above influencing factors. The best combination of each significant factor was determined by RSM design and optimum pretreatment conditions for maximum radical-scavenging capacity were established to be liquid-solid ratio of 29.19:1, extraction time of 32.13 min, and extraction temperature of 30 °C. Under these conditions, 67.60% of DPPH radical-scavenging capacity was observed experimentally, similar to the theoretical prediction of 66.36%. Full article
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588 KiB  
Review
Evolution of Analysis of Polyhenols from Grapes, Wines, and Extracts
by Bénédicte Lorrain, Isabelle Ky, Laurent Pechamat and Pierre-Louis Teissedre
Molecules 2013, 18(1), 1076-1100; https://doi.org/10.3390/molecules18011076 - 16 Jan 2013
Cited by 170 | Viewed by 13467
Abstract
Grape and wine phenolics are structurally diverse, from simple molecules to oligomers and polymers usually designated as tannins. They have an important impact on the organoleptic properties of wines, that’s why their analysis and quantification are of primordial importance. The extraction of phenolics [...] Read more.
Grape and wine phenolics are structurally diverse, from simple molecules to oligomers and polymers usually designated as tannins. They have an important impact on the organoleptic properties of wines, that’s why their analysis and quantification are of primordial importance. The extraction of phenolics from grapes and from wines is the first step involved in the analysis. Then, several analytical methods have been developed for the determination of total content of phenolic, while chromatographic and spectrophotometric analyses are continuously improved in order to achieve adequate separation of phenolic molecules, their subsequent identification and quantification. This review provides a summary of evolution of analysis of polyphenols from grapes, wines and extracts. Full article
(This article belongs to the Special Issue Methods in Polyphenol Analysis)
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218 KiB  
Review
Frontiers and Approaches to Chemical Synthesis of Oligodeoxyribonucleotides
by Tatyana Abramova
Molecules 2013, 18(1), 1063-1075; https://doi.org/10.3390/molecules18011063 - 15 Jan 2013
Cited by 21 | Viewed by 7085
Abstract
The advantages and disadvantages of existing approaches to the synthesis of oligodeoxyribonucleotides (ODN) are discussed focusing on large-scale methods. The liquid phase and solid supported synthesis and the synthesis on soluble polymers are discussed. Different problems concerning the methods and implementation of the [...] Read more.
The advantages and disadvantages of existing approaches to the synthesis of oligodeoxyribonucleotides (ODN) are discussed focusing on large-scale methods. The liquid phase and solid supported synthesis and the synthesis on soluble polymers are discussed. Different problems concerning the methods and implementation of the ODN synthesis are outlined depending on goals of using target oligomers. Full article
(This article belongs to the Section Medicinal Chemistry)
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229 KiB  
Article
Antiprotozoal Activity of Quinonemethide Triterpenes from Maytenus ilicifolia (Celastraceae)
by Vania A. F. F. M. Dos Santos, Karoline M. Leite, Mariana Da Costa Siqueira, Luis O. Regasini, Isabel Martinez, Camila T. Nogueira, Mariana Kolos Galuppo, Beatriz S. Stolf, Ana Maria Soares Pereira, Regina M. B. Cicarelli, Maysa Furlan and Marcia A. S. Graminha
Molecules 2013, 18(1), 1053-1062; https://doi.org/10.3390/molecules18011053 - 15 Jan 2013
Cited by 52 | Viewed by 7919
Abstract
The present study describes the leishmanicidal and trypanocidal activities of two quinonemethide triterpenes, maytenin (1) and pristimerin (2), isolated from Maytenus ilicifolia root barks (Celastraceae). The compounds were effective against the Trypanosomatidae Leishmania amazonensis and Leishmania chagasi and Trypanosoma [...] Read more.
The present study describes the leishmanicidal and trypanocidal activities of two quinonemethide triterpenes, maytenin (1) and pristimerin (2), isolated from Maytenus ilicifolia root barks (Celastraceae). The compounds were effective against the Trypanosomatidae Leishmania amazonensis and Leishmania chagasi and Trypanosoma cruzi, etiologic agents of leishmaniasis and Chagas’ disease, respectively. The quinonemethide triterpenes 1 and 2 exhibited a marked in vitro leishmanicidal activity against promastigotes and amastigotes with 50% inhibitory concentration (IC50) values of less than 0.88 nM. Both compounds showed IC50 lower than 0.3 nM against Trypanosoma cruzi epimastigotes. The selectivity indexes (SI) based on BALB/c macrophages for L. amazonensis and L. chagasi were 243.65 and 46.61 for (1) and 193.63 and 23.85 for (2) indicating that both compounds presented high selectivity for Leishmania sp. The data here presented suggests that these compounds should be considered in the development of new and more potent drugs for the treatment of leishmaniasis and Chagas’ disease. Full article
(This article belongs to the Special Issue Triterpenes and Triterpenoids 2013)
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511 KiB  
Article
Comparative Analysis of Thermal Behavior, Isothermal Crystallization Kinetics and Polymorphism of Palm Oil Fractions
by Xia Zhang, Lin Li, He Xie, Zhili Liang, Jianyu Su, Guoqin Liu and Bing Li
Molecules 2013, 18(1), 1036-1052; https://doi.org/10.3390/molecules18011036 - 15 Jan 2013
Cited by 52 | Viewed by 7217
Abstract
Thermal behavior of palm stearin (PS) and palm olein (PO) was explored by monitoring peak temperature transitions by differential scanning calorimetry (DSC). The fatty acid composition (FAC), isothermal crystallization kinetics studied by pulsed Nuclear Magnetic Resonance (pNMR) and isothermal microstructure were also compared. [...] Read more.
Thermal behavior of palm stearin (PS) and palm olein (PO) was explored by monitoring peak temperature transitions by differential scanning calorimetry (DSC). The fatty acid composition (FAC), isothermal crystallization kinetics studied by pulsed Nuclear Magnetic Resonance (pNMR) and isothermal microstructure were also compared. The results indicated that the fatty acid composition had an important influence on the crystallization process. PS and PO both exhibited more multiple endotherms than exotherms which showed irregular peak shapes. An increasing in cooling rate, generally, was associated with an increase in peak size. Application of the Avaimi equation to isothermal crystallization of PS and PO revealed different nucleation and growth mechanisms based on the Avrami exponents. PS quickly reached the end of crystallization because of more saturated triacylglycerol (TAG). The Avrami index of PS were the same as PO under the same isothermal condition at lower temperatrue, indicating that the crystallization mechanism of the two samples based on super-cooling state were the same. According to the polarized light microscope (PLM) images, crystal morphology of PS and PO was different. With the temperature increased, the structure of crystal network of both PS and PO gradually loosened. Full article
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2589 KiB  
Article
Chitosan Rate of Uptake in HEK293 Cells is Influenced by Soluble versus Microparticle State and Enhanced by Serum-Induced Cell Metabolism and Lactate-Based Media Acidification
by Caroline D. Hoemann, Jessica Guzmán-Morales, Nicolas Tran-Khanh, Geneviève Lavallée, Mario Jolicoeur and Marc Lavertu
Molecules 2013, 18(1), 1015-1035; https://doi.org/10.3390/molecules18011015 - 15 Jan 2013
Cited by 22 | Viewed by 7256
Abstract
Chitosan is a biocompatible polysaccharide composed of glucosamine and N-acetylglucosamine. The polymer has a unique behavior of fluctuating between soluble chains at pH 6 and insoluble microparticles at pH 7. The purpose of this study was to test the hypothesis that chitosan [...] Read more.
Chitosan is a biocompatible polysaccharide composed of glucosamine and N-acetylglucosamine. The polymer has a unique behavior of fluctuating between soluble chains at pH 6 and insoluble microparticles at pH 7. The purpose of this study was to test the hypothesis that chitosan structure, solubility state, and serum influence the rate of cell uptake. Chitosans with 80% and 95% degree of deacetylation (medium and low viscosity) were tagged with rhodamine and analyzed for particle size, media solubility, and uptake by HEK293 epithelial cells using live confocal microscopy and flow cytometry. In media pH 7.4 with or without 10% serum, chitosans fully precipitated into 0.5 to 1.4 µm diameter microparticles with a slight negative charge. During 24 h of culture in serum-free medium, chitosan particles remained extracellular. In cultures with serum, particles were taken up into intracellular vesicles in a serum dose-dependent manner. Opsonization of chitosan with serum, or replacement of serum by epidermal growth factor (EGF) failed to mediate serum-free chitosan particle uptake. Serum stimulated cells to acidify the media, partly by lactate generation. Media acidified to pH 6.5 by 7 mM lactate maintained 50% of chitosan in the soluble fraction, and led to minor uniform serum-free uptake in small vesicles. Conclusion: Media acidification mediates minor in vitro uptake of non-biofouled soluble chitosan chains, while serum-biofouled insoluble chitosan microparticles require sustained serum exposure to generate energy required for macropinocytosis. Full article
(This article belongs to the Special Issue Chitins and Chitosans)
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705 KiB  
Article
Supercritical Carbon Dioxide Extraction of Seed Oil from Winter Melon (Benincasa hispida) and Its Antioxidant Activity and Fatty Acid Composition
by Mandana Bimakr, Russly Abdul Rahman, Farah Saleena Taip, Noranizan Mohd Adzahan, Md. Zaidul Islam Sarker and Ali Ganjloo
Molecules 2013, 18(1), 997-1014; https://doi.org/10.3390/molecules18010997 - 15 Jan 2013
Cited by 54 | Viewed by 8271
Abstract
In the present study, supercritical carbon dioxide (SC-CO2) extraction of seed oil from winter melon (Benincasa hispida) was investigated. The effects of process variables namely pressure (150–300 bar), temperature (40–50 °C) and dynamic extraction time (60–120 min) on crude [...] Read more.
In the present study, supercritical carbon dioxide (SC-CO2) extraction of seed oil from winter melon (Benincasa hispida) was investigated. The effects of process variables namely pressure (150–300 bar), temperature (40–50 °C) and dynamic extraction time (60–120 min) on crude extraction yield (CEY) were studied through response surface methodology (RSM). The SC-CO2 extraction process was modified using ethanol (99.9%) as co-solvent. Perturbation plot revealed the significant effect of all process variables on the CEY. A central composite design (CCD) was used to optimize the process conditions to achieve maximum CEY. The optimum conditions were 244 bar pressure, 46 °C temperature and 97 min dynamic extraction time. Under these optimal conditions, the CEY was predicted to be 176.30 mg-extract/g-dried sample. The validation experiment results agreed with the predicted value. The antioxidant activity and fatty acid composition of crude oil obtained under optimized conditions were determined and compared with published results using Soxhlet extraction (SE) and ultrasound assisted extraction (UAE). It was found that the antioxidant activity of the extract obtained by SC-CO2 extraction was strongly higher than those obtained by SE and UAE. Identification of fatty acid composition using gas chromatography (GC) showed that all the extracts were rich in unsaturated fatty acids with the most being linoleic acid. In contrast, the amount of saturated fatty acids extracted by SE was higher than that extracted under optimized SC-CO2 extraction conditions. Full article
(This article belongs to the Section Natural Products Chemistry)
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455 KiB  
Article
Comparative ANNs with Different Input Layers and GA-PLS Study for Simultaneous Spectrofluorimetric Determination of Melatonin and Pyridoxine HCl in the Presence of Melatonin’s Main Impurity
by Hany W. Darwish, Mohamed I. Attia, Ali S. Abdelhameed, Amer M. Alanazi and Ahmed H. Bakheit
Molecules 2013, 18(1), 974-996; https://doi.org/10.3390/molecules18010974 - 14 Jan 2013
Cited by 16 | Viewed by 4878
Abstract
Melatonin (MLT) has many health implications, therefore it is important to develop specific analytical methods for the determination of MLT in the presence of its main impurity, N-{2-[1-({3-[2-(acetylamino)ethyl]-5-methoxy-1H-indol-2-yl}methyl)-5-methoxy-1H-indol-3-yl]ethyl}acetaamide (DMLT) and pyridoxine HCl (PNH) as a co-formulated drug. This [...] Read more.
Melatonin (MLT) has many health implications, therefore it is important to develop specific analytical methods for the determination of MLT in the presence of its main impurity, N-{2-[1-({3-[2-(acetylamino)ethyl]-5-methoxy-1H-indol-2-yl}methyl)-5-methoxy-1H-indol-3-yl]ethyl}acetaamide (DMLT) and pyridoxine HCl (PNH) as a co-formulated drug. This work describes simple, sensitive, and reliable four multivariate calibration methods, namely artificial neural network preceded by genetic algorithm (GA-ANN), principal component analysis (PCA-ANN) and wavelet transform procedures (WT-ANN) as well as partial least squares preceded by genetic algorithm (GA-PLS) for the spectrofluorimetric determination of MLT and PNH in the presence of DMLT. Analytical performance of the proposed methods was statistically validated with respect to linearity, accuracy, precision and specificity. The proposed methods were successfully applied for the assay of MLT in laboratory prepared mixtures containing up to 15% of DMLT and in commercial MLT tablets with recoveries of no less than 99.00%. No interference was observed from common pharmaceutical additives and the results compared favorably with those obtained by a reference method. Full article
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225 KiB  
Article
Chemical Composition and Antibacterial Activity of Essential Oils from Different Parts of Leonurus japonicus Houtt.
by Liang Xiong, Cheng Peng, Qin-Mei Zhou, Feng Wan, Xiao-Fang Xie, Li Guo, Xiao-Hong Li, Cheng-Jun He and Ou Dai
Molecules 2013, 18(1), 963-973; https://doi.org/10.3390/molecules18010963 - 14 Jan 2013
Cited by 74 | Viewed by 9005
Abstract
The herb and fruits of Leonurus japonicus Houtt., named “Yimucao” and “Chongweizi”, respectively, in Chinese, have been widely used in China as gynecological medicines. The components of the essential oils obtained by hydrodistillation were investigated by GC-MS. The antibacterial activity of the essential [...] Read more.
The herb and fruits of Leonurus japonicus Houtt., named “Yimucao” and “Chongweizi”, respectively, in Chinese, have been widely used in China as gynecological medicines. The components of the essential oils obtained by hydrodistillation were investigated by GC-MS. The antibacterial activity of the essential oils was determined by micro-dilution assay. The results showed large variations in the chemical composition and antibacterial activity of the oils. The oil of “Yimucao” showed antibacterial activity against various Gram-positive bacteria and consisted mainly of sesquiterpenes and diterpenes, with phytone, phytol, caryophyllene oxide and β-caryophyllene being the most significant constituents, whereas the oil of “Chongweizi”, mainly made up of bornyl acetate and aliphatic hydrocarbons, was inactive in the antibacterial assay. Further study of the main compounds in “Yimucao oil” showed that β-caryophyllene had wide-spectrum activity against Gram-positive bacteria. Full article
(This article belongs to the Section Natural Products Chemistry)
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257 KiB  
Article
Investigating the Antioxidant and Acetylcholinesterase Inhibition Activities of Gossypium herbaceam
by Yongxin Zhao, Jun Dou, Tao Wu and Haji Akber Aisa
Molecules 2013, 18(1), 951-962; https://doi.org/10.3390/molecules18010951 - 14 Jan 2013
Cited by 67 | Viewed by 8144
Abstract
Our previous research showed that standardized extract from the flowers of the Gossypium herbaceam labeled GHE had been used in clinical trials for its beneficial effects on brain functions, particularly in connection with age-related dementia and Alzheimer’s disease (AD). The aim of this [...] Read more.
Our previous research showed that standardized extract from the flowers of the Gossypium herbaceam labeled GHE had been used in clinical trials for its beneficial effects on brain functions, particularly in connection with age-related dementia and Alzheimer’s disease (AD). The aim of this work was to determine the components of this herb and the individual constituents of GHE. In order to better understand this herb for AD treatment, we investigated the acetylcholinesterase (AChE) inhibition and antioxidant activity of GHE as well as the protective effects to PC12 cells against cytotoxicity induced by tertiary butyl hydroperoxide (tBHP) using in vitro assays. The antioxidant activities were assessed by measuring their capabilities for scavenging 1,1-diphenyl-2-picylhydrazyl (DPPH) and 2-2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical as well as in inhibiting lipid peroxidation. Our data showed that GHE exhibited certain activities against AChE and also is an efficient free radical scavenger, which may be helpful in preventing or alleviating patients suffering from AD. Full article
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831 KiB  
Article
Total Flavonoids of Scutellaria barbata Inhibit Invasion of Hepatocarcinoma via MMP/TIMP in Vitro
by Zhi-Jun Dai, Bao-Feng Wang, Wang-Feng Lu, Zhi-Dong Wang, Xiao-Bin Ma, Wei-Li Min, Hua-Feng Kang, Xi-Jing Wang and Wen-Ying Wu
Molecules 2013, 18(1), 934-950; https://doi.org/10.3390/molecules18010934 - 11 Jan 2013
Cited by 39 | Viewed by 6271
Abstract
Metastasis is the major cause of cancer-related deaths. Targeting the process of metastasis has been proposed as a strategy to fight cancer. Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is used for treatment of many diseases, including cancer. [...] Read more.
Metastasis is the major cause of cancer-related deaths. Targeting the process of metastasis has been proposed as a strategy to fight cancer. Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is used for treatment of many diseases, including cancer. This study aimed to determine the anti-metastatic effect of total flavonoids of S. barbata (TF-SB) using the human hepatocarcinoma MHCC97H cell line with high metastatic potential. Our results show that TF-SB could significantly inhibit the proliferation and invasion of MHCC97H cells in a dose-dependent manner. MMP-2 and MMP-9 expression were obviously decreased after TF-SB treatment at both the mRNA and protein level. TIMP-1 and TIMP-2 expression were simultaneously increased. The present study indicates that TF-SB could reduce the metastatic capability of MHCC97H cell, probably through decrease of the MMP expression, and simultaneous increase of the TIMP expression. Full article
(This article belongs to the Section Natural Products Chemistry)
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315 KiB  
Article
Synthesis of 5α-Androstane-17-spiro-δ-lactones with a 3-Keto, 3-Hydroxy, 3-Spirocarbamate or 3-Spiromorpholinone as Inhibitors of 17β-Hydroxysteroid Dehydrogenases
by Guy Bertrand Djigoué, Béatrice Tchédam Ngatcha, Jenny Roy and Donald Poirier
Molecules 2013, 18(1), 914-933; https://doi.org/10.3390/molecules18010914 - 11 Jan 2013
Cited by 10 | Viewed by 6377
Abstract
We synthesized two series of androstane derivatives as inhibitors of type 3 and type 5 17β-hydroxysteroid dehydrogenases (17β-HSDs). In the first series, four monospiro derivatives at position C17 were prepared from androsterone (ADT) or epi-ADT. After the protection of the alcohol at [...] Read more.
We synthesized two series of androstane derivatives as inhibitors of type 3 and type 5 17β-hydroxysteroid dehydrogenases (17β-HSDs). In the first series, four monospiro derivatives at position C17 were prepared from androsterone (ADT) or epi-ADT. After the protection of the alcohol at C3, the C17-ketone was alkylated with the lithium acetylide of tetrahydro-2-(but-3-ynyl)-2-H-pyran, the triple bond was hydrogenated, the protecting groups hydrolysed and the alcohols oxidized to give the corresponding 3-keto-17-spiro-lactone derivative. The other three compounds were generated from this keto-lactone by reducing the ketone at C3, or by introducing one or two methyl groups. In the second series, two dispiro derivatives at C3 and C17 were prepared from epi-ADT. After introducing a spiro-δ-lactone at C17 and an oxirane at C3, an aminolysis of the oxirane with L-isoleucine methyl ester provided an amino alcohol, which was treated with triphosgene or sodium methylate to afford a carbamate- or a morpholinone-androstane derivative, respectively. These steroid derivatives inhibited 17β-HSD3 (14–88% at 1 μM; 46–94% at 10 μM) and 17β-HSD5 (54–73% at 0.3 μM; 91–92% at 3 μM). They did not produce any androgenic activity and did not bind steroid (androgen, estrogen, glucocorticoid and progestin) receptors, suggesting a good profile for prostate cancer therapy. Full article
(This article belongs to the Special Issue Spiro Compounds)
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371 KiB  
Article
Dibenzo[1,2,5]thiadiazepines Are Non-Competitive GABAA Receptor Antagonists
by Juan F. Ramírez-Martínez, Rodolfo González-Chávez, Raquel Guerrero-Alba, Paul E. Reyes-Gutiérrez, Roberto Martínez, Marcela Miranda-Morales, Rosa Espinosa-Luna, Marco M. González-Chávez and Carlos Barajas-López
Molecules 2013, 18(1), 894-913; https://doi.org/10.3390/molecules18010894 - 11 Jan 2013
Cited by 6 | Viewed by 8156
Abstract
A new process for obtaining dibenzo[c,f][1,2,5]thiadiazepines (DBTDs) and their effects on GABAA receptors of guinea pig myenteric neurons are described. Synthesis of DBTD derivatives began with two commercial aromatic compounds. An azide group was obtained after two sequential reactions, and the central [...] Read more.
A new process for obtaining dibenzo[c,f][1,2,5]thiadiazepines (DBTDs) and their effects on GABAA receptors of guinea pig myenteric neurons are described. Synthesis of DBTD derivatives began with two commercial aromatic compounds. An azide group was obtained after two sequential reactions, and the central ring was closed via a nitrene to obtain the tricyclic sulfonamides (DBTDs). Whole-cell recordings showed that DBTDs application did not affect the holding current but inhibited the currents induced by GABA (IGABA), which are mediated by GABAA receptors. These DBTDs effects reached their maximum 3 min after application and were: (i) reversible, (ii) concentration-dependent (with a rank order of potency of 2c = 2d > 2b), (iii) mediated by a non-competitive antagonism, and (iv) only observed when applied extracellularly. Picrotoxin (which binds in the channel mouth) and DBTDs effects were not modified when both substances were simultaneous applied. Our results indicate that DBTD acted on the extracellular domain of GABAA channels but independent of the picrotoxin, benzodiazepine, and GABA binding sites. DBTDs used here could be the initial model for synthesizing new GABAA receptor inhibitors with a potential to be used as antidotes for positive modulators of these receptors or to induce experimental epilepsy. Full article
(This article belongs to the Section Medicinal Chemistry)
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857 KiB  
Article
Synthesis, Crystal Structure, Vibration Spectral, and DFT Studies of 4-Aminoantipyrine and Its Derivatives
by Yi Li, Yuanyuan Liu, Haowei Wang, Xiaohui Xiong, Ping Wei and Fangshi Li
Molecules 2013, 18(1), 877-893; https://doi.org/10.3390/molecules18010877 - 11 Jan 2013
Cited by 83 | Viewed by 8213
Abstract
Three compounds derived from 4-aminoantipyrine (AA) were synthesized and their structures confirmed by melting point, elemental analysis, FT-IR, and 1H-NMR. The molecular structures of the four compounds were characterized by single-crystal X-ray diffraction and calculated by using the density functional theory (DFT) [...] Read more.
Three compounds derived from 4-aminoantipyrine (AA) were synthesized and their structures confirmed by melting point, elemental analysis, FT-IR, and 1H-NMR. The molecular structures of the four compounds were characterized by single-crystal X-ray diffraction and calculated by using the density functional theory (DFT) method with 6-31G (d) basis set. The calculated molecular geometries and the vibration frequencies of the AA derivatives in the ground state have been compared with the experimental data. The results show that the optimized geometries can reproduce well the crystal structural parameters, and the theoretical vibration frequencies show good agreement with the experimental data, although the experimental data are different from the theoretical ones due to the intermolecular forces. Besides, the molecular electrostatic potential (MEP) and the frontier molecular orbital (FMO) analysis of the compounds were investigated by theoretical calculations. Full article
(This article belongs to the Section Molecular Diversity)
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