Molecules

590 KiB

Open AccessArticle

Bioactivity-Guided Isolation of Ethyl-p-methoxycinnamate, an Anti-inflammatory Constituent, from Kaempferia galanga L. Extracts

by Muhammad Ihtisham Umar, Mohd Zaini Asmawi, Amirin Sadikun, Item J. Atangwho, Mun Fei Yam, Rabia Altaf and Ashfaq Ahmed

Molecules 2012, 17(7), 8720-8734; https://doi.org/10.3390/molecules17078720 - 23 Jul 2012

Cited by 76 | Viewed by 9289

Abstract

This study evaluated the anti-inflammatory effect of Kaempferia galanga (KG) using an activity-guided approach. KG rhizomes were serially extracted with petroleum ether, chloroform, methanol and water. These extracts (2 g/kg each) were tested for their ability to inhibit carrageenan-induced rat paw edema. The [...] Read more.

This study evaluated the anti-inflammatory effect of Kaempferia galanga (KG) using an activity-guided approach. KG rhizomes were serially extracted with petroleum ether, chloroform, methanol and water. These extracts (2 g/kg each) were tested for their ability to inhibit carrageenan-induced rat paw edema. The chloroform extract was found to exert the highest inhibition (42.9%) compared to control (p < 0.001), hence it was further fractionated by washing serially with hexane, hexane-chloroform (1:1) and chloroform. The chloroform fraction (1 g/kg) showed the highest inhibitory effect (51.9%, p < 0.001) on carrageenan-induced edema. This chloroform fraction was further fractionated with hexane-chloroform (1:3) and chloroform, and of the two fractions, the hexane-chloroform sub-fraction was the most effective in inhibiting edema (53.7%, p < 0.001). GC-MS analysis of the active sub-fraction identified ethyl-p-methoxycinnamate (EPMC) as the major component, which was re-crystallized. EPMC dose-dependently inhibited carrageenan-induced edema with an MIC of 100 mg/kg. Moreover, in an in vitro study, EPMC non-selectively inhibited the activities of cyclooxygenases 1 and 2, with IC₅₀ values of 1.12 µM and 0.83 µM respectively. These results validate the anti-inflammatory activity of KG which may be exerted by the inhibition of cyclooxygenases 1 and 2. EPMC isolated from this plant may be the active anti-inflammatory agent. Full article

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320 KiB

Open AccessReview

Supercritical Synthesis of Biodiesel

by Juana M. Bernal, Pedro Lozano, Eduardo García-Verdugo, M. Isabel Burguete, Gregorio Sánchez-Gómez, Gregorio López-López, Mathieu Pucheault, Michel Vaultier and Santiago V. Luis

Molecules 2012, 17(7), 8696-8719; https://doi.org/10.3390/molecules17078696 - 23 Jul 2012

Cited by 76 | Viewed by 9824

Abstract

The synthesis of biodiesel fuel from lipids (vegetable oils and animal fats) has gained in importance as a possible source of renewable non-fossil energy in an attempt to reduce our dependence on petroleum-based fuels. The catalytic processes commonly used for the production of [...] Read more.

The synthesis of biodiesel fuel from lipids (vegetable oils and animal fats) has gained in importance as a possible source of renewable non-fossil energy in an attempt to reduce our dependence on petroleum-based fuels. The catalytic processes commonly used for the production of biodiesel fuel present a series of limitations and drawbacks, among them the high energy consumption required for complex purification operations and undesirable side reactions. Supercritical fluid (SCF) technologies offer an interesting alternative to conventional processes for preparing biodiesel. This review highlights the advances, advantages, drawbacks and new tendencies involved in the use of supercritical fluids (SCFs) for biodiesel synthesis. Full article

(This article belongs to the Special Issue Synthesis and Extraction in Supercritical Fluids)

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617 KiB

Open AccessCommunication

Buddleja officinalis Maximowicz Extract Inhibits Lipid Accumulation on Adipocyte Differentiation in 3T3-L1 Cells and High-Fat Mice

by Changhyun Roh, Min-Kyoung Park, Hee-June Shin, Uhee Jung and Jin-Kyu Kim

Molecules 2012, 17(7), 8687-8695; https://doi.org/10.3390/molecules17078687 - 23 Jul 2012

Cited by 9 | Viewed by 5590

Abstract

Obesity is a global health problem. It is also known to be a risk factor for the development of metabolic disorders, type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis. In this study, we elucidated that Buddleja officinalis Maximowicz extract significantly inhibited [...] Read more.

Obesity is a global health problem. It is also known to be a risk factor for the development of metabolic disorders, type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis. In this study, we elucidated that Buddleja officinalis Maximowicz extract significantly inhibited lipid accumulation during 3T3-L1 adipocyte differentiation. Furthermore, Buddleja officinalis Maximowicz extract reduced the body weight gain induced through feeding a high-fat diet to C57BL/6 mice. The treatment of Buddleja officinalis Maximowicz extract significantly reduced the adipose tissue weight to 2.7/100 g of body weight in high-fat mice. When their adipose tissue morphology was investigated for histochemical staining, the distribution of cell size in the high-fat diet groups was hypertrophied compared with those from Buddleja officinalis Maximowicz extract-treated mice. In addition, in Buddleja officinalis Maximowicz extract-treated mice, a significant reduction of serum triglyceride and T-cholesterol was observed at to 21% and 17%, respectively. The discovery of bioactive compounds from diet or dietary supplementation is one of possible ways to control obesity and to prevent or reduce the risks of various obesity-related diseases. These results support that Buddleja officinalis Maximowicz extract is expected to create the therapeutic interest with respect to the treatment of obesity. Full article

(This article belongs to the Section Natural Products Chemistry)

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252 KiB

Open AccessArticle

Ultrasound-Promoted One-Pot, Three-Component Synthesis of Spiro[indoline-3,1'-pyrazolo[1,2-b]phthalazine] Derivatives

by Juxian Wang, Xiaoguang Bai, Changliang Xu, Yucheng Wang, Wei Lin, Yi Zou and Daqing Shi

Molecules 2012, 17(7), 8674-8686; https://doi.org/10.3390/molecules17078674 - 23 Jul 2012

Cited by 30 | Viewed by 6134

Abstract

A series of 3'-aminospiro[indoline-3,1'-pyrazolo[1,2-b]phthalazine]-2,5',10'-trione derivatives have been synthesized by a one-pot three-component reaction of isatin, malononitrile or ethyl cyanoacetate and phthalhydrazide catalyzed by piperidine under ultrasound irradiation. For comparison the reactions were carried out under both conventional and ultrasonic conditions. In [...] Read more.

A series of 3'-aminospiro[indoline-3,1'-pyrazolo[1,2-b]phthalazine]-2,5',10'-trione derivatives have been synthesized by a one-pot three-component reaction of isatin, malononitrile or ethyl cyanoacetate and phthalhydrazide catalyzed by piperidine under ultrasound irradiation. For comparison the reactions were carried out under both conventional and ultrasonic conditions. In general, improvement in rates and yields were observed when the reactions were carried out under sonication compared with classical conditions. Full article

(This article belongs to the Special Issue Heterocycles)

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Graphical abstract

248 KiB

Open AccessArticle

Synthesis, Characterization, Antibacterial and Antifungal Evaluation of Novel Monosaccharide Esters

by Yi Shen, Yufeng Sun, Zhipei Sang, Chengjun Sun, Ya Dai and Yong Deng

Molecules 2012, 17(7), 8661-8673; https://doi.org/10.3390/molecules17078661 - 23 Jul 2012

Cited by 12 | Viewed by 5756

Abstract

A novel series of 3-(2-furyl)acrylate monosaccharide esters Ia–f and menthyloxycarbonyl monosaccharide esters IIa–f were designed and synthesized. The chemical structures of the target compounds were confirmed by IR, ¹H- and ¹³C-NMR and ESI-MS, and the target compounds [...] Read more.

A novel series of 3-(2-furyl)acrylate monosaccharide esters Ia–f and menthyloxycarbonyl monosaccharide esters IIa–f were designed and synthesized. The chemical structures of the target compounds were confirmed by IR, ¹H- and ¹³C-NMR and ESI-MS, and the target compounds were investigated for their in vitro antibacterial and antifungal activities. The antibacterial screening results showed that the 3-(2-furyl)acrylate monosaccharide ester derivatives Ia–f were either inactive or only weakly active against the three Gram-positive bacterial strains tested, whereas the menthyloxycarbonyl monosaccharide ester derivatives IIa–f exhibited higher levels of activity, with compound IIe being especially potent. The results of the antifungal screening revealed that compounds Ib, Ie, IIb and IIc displayed potent in vitro activities, whereas If and IIf showed promising activities against all of the microorganisms tested, with If exhibiting levels of activity deserving of further investigation. Full article

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532 KiB

Open AccessArticle

Solid-State Synthesis of Poly(3',4'-dimethoxy-2,2':5',2"- terthiophene): Comparison With Poly(terthiophene) and Poly(3',4'-ethylenedioxy-2,2':5',2"- terthiophene)

by Tursun Abdiryim, Ruxangul Jamal, Aminam Ubul and Ismayil Nurulla

Molecules 2012, 17(7), 8647-8660; https://doi.org/10.3390/molecules17078647 - 23 Jul 2012

Cited by 14 | Viewed by 5933

Abstract

A new terthiophene monomer: 3',4'-dimethoxy-2,2':5',2"-terthiophene (TMT) was synthesized and characterized by ¹H-NMR, ¹³C-NMR and FTIR. The solid-state oxidative polymerizations of TMT were performed in various ratios of oxidant (FeCl₃) to monomer (TMT). The resulting polymers were characterized by ¹ [...] Read more.

A new terthiophene monomer: 3',4'-dimethoxy-2,2':5',2"-terthiophene (TMT) was synthesized and characterized by ¹H-NMR, ¹³C-NMR and FTIR. The solid-state oxidative polymerizations of TMT were performed in various ratios of oxidant (FeCl₃) to monomer (TMT). The resulting polymers were characterized by ¹H-NMR, FTIR, UV-vis-NIR, GPC, X-ray diffraction, CV, as well as TGA and conductivity measurements. The structure and properties of poly (TMT) were compared with those of polyterthiophene [poly(TT)] and poly (3',4'-ethylenedioxy-2,2':5',2"-terthiophene) [poly(TET)] prepared under the same polymerization conditions. After comparative analysis with poly(TT) and poly(TET), the effects of the dimethoxy substituent and FeCl₃ on the structural and physicochemical properties of the poly(TMT)s were discussed in depth. The comparison suggested that the dimethoxy-substituted polymer did not display higher crystallinity, thermal stability, conductivity and electrochemical activity than ethylenedioxy substituted one. The results also showed that the effect of FeCl₃ on poly(TMT) was similar that seen with the poly(TT), in which the oxidation degree, electrochemical activity and conductivity increased steadily with increasing [FeCl₃]/[TT] ratio. Furthermore, the poly(TMT) and poly(TT) are mostly made up of dimers with a small amount of higher molecular weight components. Full article

(This article belongs to the Section Organic Chemistry)

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827 KiB

Open AccessArticle

Anti-Hepatitis B Virus Activity of Chickweed [Stellaria media (L.) Vill.] Extracts in HepG2.2.15 Cells

by Lihua Ma, Jie Song, Yaqin Shi, Changmei Wang, Bin Chen, Donghao Xie and Xiaobin Jia

Molecules 2012, 17(7), 8633-8646; https://doi.org/10.3390/molecules17078633 - 18 Jul 2012

Cited by 22 | Viewed by 8443

Abstract

Stellaria media (Linn.) Villars is a traditional Chinese medicine that has been used for over 200 years, mainly for the treatment of dermatitis and other skin diseases. It has also been used as an anti-viral agent. All the fresh chickweed juice samples used [...] Read more.

Stellaria media (Linn.) Villars is a traditional Chinese medicine that has been used for over 200 years, mainly for the treatment of dermatitis and other skin diseases. It has also been used as an anti-viral agent. All the fresh chickweed juice samples used in this study were prepared using macroporous resin and ultrafiltration technology. The anti-hepatitis B virus (HBV) activity of S. media was evaluated in vitro using the human HBV-transfected liver cell line HepG2.2.15. The concentrations of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in HepG2.2.15 cell culture medium were determined by enzyme-linked immunosorbent assay (ELISA) after S. media-n (SM-n) treatment for 6 or 9 days. HBV DNA was quantified using transcription-mediated amplification and real-time polymerase chain reaction. In HepG2.2.15 cells, 30 μg/mL SM-3 effectively suppressed the secretion of HBsAg and HBeAg with inhibition rates of 27.92% and 25.35% after 6 days of treatment, respectively. Consistent with the reduction in HBV antigens, SM-3 also reduced the level of HBV DNA in a dose-dependent manner. The characterization and quantitation of the chemical composition of SM-3 showed the presence of flavonoid C-glycosides, polysaccharides, and protein, which exhibited diverse antiviral activities. In conclusion, our results demonstrate that SM-3 possesses potential anti-HBV activity in vitro. This is the first report demonstrating the anti-HBV effects of S. media, which is currently under early development as a potential anti-HBV drug candidate. Full article

(This article belongs to the Section Natural Products Chemistry)

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768 KiB

Open AccessArticle

Metabolism of Tanshinone IIA, Cryptotanshinone and Tanshinone I from Radix Salvia Miltiorrhiza in Zebrafish

by Yingjie Wei, Ping Li, Changmei Wang, Yunru Peng, Luan Shu, Xiaobin Jia, Wenquan Ma and Bing Wang

Molecules 2012, 17(7), 8617-8632; https://doi.org/10.3390/molecules17078617 - 18 Jul 2012

Cited by 28 | Viewed by 6707

Abstract

The study aimed to investigate the potential of zebrafish in imitating mammal phase I metabolism of natural compounds. Three diterpenoid quinones from Radix Salvia miltiorrhiza, namely tanshinone IIA (TIIA), cryptotanshinone (Cry) and tanshinone I (TI) were selected as model compounds, and their metabolites [...] Read more.

The study aimed to investigate the potential of zebrafish in imitating mammal phase I metabolism of natural compounds. Three diterpenoid quinones from Radix Salvia miltiorrhiza, namely tanshinone IIA (TIIA), cryptotanshinone (Cry) and tanshinone I (TI) were selected as model compounds, and their metabolites mediated by zebrafish were characterized using a high-performance liquid chromatography coupled ion-trap mass spectrometry (HPLC/IT-MSn) method with electrospray ionization in positive mode. The separation was performed with a Zorbax C-18 column using a binary gradient elution of 0.05% formic acid acetonitrile/0.05% formic acid water. According to the MS spectra and after comparison with reference standards and literature reports, hydroxylation, dehydrogenation or D-ring hydrolysis metabolites of TIIA and Cry but not of TI were characterized, which coincided with those reported using regular in vivo or in vitro metabolic analysis methods, thus verifying that zebrafish can successfully imitate mammalian phase I metabolism which instills further confidence in using zebrafish as a novel and prospective metabolism model. Full article

(This article belongs to the Section Medicinal Chemistry)

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318 KiB

Open AccessCommunication

IBS-Catalyzed Regioselective Oxidation of Phenols to 1,2-Quinones with Oxone^®

by Muhammet Uyanik, Tatsuya Mutsuga and Kazuaki Ishihara

Molecules 2012, 17(7), 8604-8616; https://doi.org/10.3390/molecules17078604 - 18 Jul 2012

Cited by 64 | Viewed by 10988

Abstract

We have developed the first example of hypervalent iodine(V)-catalyzed regioselective oxidation of phenols to o-quinones. Various phenols could be oxidized to the corresponding o-quinones in good to excellent yields using catalytic amounts of sodium salts of 2-iodobenzenesulfonic acids (pre-IBSes) [...] Read more.

We have developed the first example of hypervalent iodine(V)-catalyzed regioselective oxidation of phenols to o-quinones. Various phenols could be oxidized to the corresponding o-quinones in good to excellent yields using catalytic amounts of sodium salts of 2-iodobenzenesulfonic acids (pre-IBSes) and stoichiometric amounts of Oxone^® as a co-oxidant under mild conditions. The reaction rate of IBS-catalyzed oxidation under nonaqueous conditions was further accelerated in the presence of an inorganic base such as potassium carbonate (K₂CO₃), a phase transfer catalyst such as tetrabutylammonium hydrogen sulfate (nBu₄NHSO₄), and a dehydrating agent such as anhydrous sodium sulfate (Na₂SO₄). Full article

(This article belongs to the Special Issue Hypervalent Compounds)

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392 KiB

Open AccessArticle

Effect of β-Carotene on Immunity Function and Tumour Growth in Hepatocellular Carcinoma Rats

by Bokang Cui, Su Liu, Qibo Wang and Xiaojun Lin

Molecules 2012, 17(7), 8595-8603; https://doi.org/10.3390/molecules17078595 - 18 Jul 2012

Cited by 23 | Viewed by 5343

Abstract

The aim of the present study was to investigate the anticancer and immunity activity of β-carotene in hepatocellular carcinoma (HCC) rats. Three days after transplantation, forty Wistar rats were randomly divided into four groups, each group consisting of 10 animals. These groups were [...] Read more.

The aim of the present study was to investigate the anticancer and immunity activity of β-carotene in hepatocellular carcinoma (HCC) rats. Three days after transplantation, forty Wistar rats were randomly divided into four groups, each group consisting of 10 animals. These groups were control group (untreated), low-dose β-carotene-treated group (20 mg/kg), middle-dose group (40 mg/kg) and high-dose (60 mg/kg) group. β-Carotene-treated groups were fed with β-carotene (20, 40, 60 mg/kg b.w.) orally for 30 days. Control group was treated with the same volume of physiological saline. Another ten rats were served as the normal group. Results showed that 30 days of β-carotene treatment could significantly inhibit tumour growth, enhance blood NK, IL-2, TNF-α, WBC, TP, ALB and A/G levels, and decrease blood ALT, AST and ALP activities in HCC rats. Pathological analysis of liver tissue showed that β-carotene treatment may decrease damage of liver tissue in HCC rats. It can be concluded that β-carotene may improve the immunity function and inhibit tumour growth in HCC rats. Full article

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205 KiB

Open AccessArticle

Effect of Curing Agent and Temperature on the Rheological Behavior of Epoxy Resin Systems

by Chenhui Zhao, Guangcheng Zhang and Lei Zhao

Molecules 2012, 17(7), 8587-8594; https://doi.org/10.3390/molecules17078587 - 17 Jul 2012

Cited by 26 | Viewed by 7184

Abstract

The effect of curing agent (6610) content and temperature on the rheological behavior of the epoxy resin CYD-128 was studied by DSC analysis and viscosity experiments. The results show that the resin system meets the requirements of processing technology. A complete reaction occurs [...] Read more.

The effect of curing agent (6610) content and temperature on the rheological behavior of the epoxy resin CYD-128 was studied by DSC analysis and viscosity experiments. The results show that the resin system meets the requirements of processing technology. A complete reaction occurs when the curing agent content (40 parts per hundred resin, phr) is a little higher than the theoretical value (33.33 phr), while the degree of reaction of the resin system is reduced when the curing agent content is lower (25.00 phr) than theoretical value. However, excessive curing agent (50.00 phr) results in a lower reaction rate. Curing agent content has little influence on gel time when curing agent content exceeded 33.33 phr and the temperature was less than 70 °C. The isothermal viscosity-time curves shift towards the –x axis when the temperature rises from 50 °C to 80 °C. Meanwhile, higher temperature results in higher reaction rates. Full article

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170 KiB

Open AccessArticle

A Facile and Efficient Procedure for the Synthesis of New Benzimidazole-2-thione Derivatives

by Augusto Rivera, Mauricio Maldonado and Jaime Ríos-Motta

Molecules 2012, 17(7), 8578-8586; https://doi.org/10.3390/molecules17078578 - 17 Jul 2012

Cited by 6 | Viewed by 5135

Abstract

A series of benzimidazole-2-thione derivatives was synthesized using a reaction between the macrocyclic aminal 16H,13H-5:12,7:14-dimethanedibenzo[d,i]-[1,3,6,8] tetraazecine (DMDBTA, 5) and various nucleophiles in the presence of carbon disulfide. A full chemical characterization using IR, ¹H-, ¹³ [...] Read more.

A series of benzimidazole-2-thione derivatives was synthesized using a reaction between the macrocyclic aminal 16H,13H-5:12,7:14-dimethanedibenzo[d,i]-[1,3,6,8] tetraazecine (DMDBTA, 5) and various nucleophiles in the presence of carbon disulfide. A full chemical characterization using IR, ¹H-, ¹³C-NMR and GC-MS analyses of the new compounds is provided. These compounds were separated from the reaction mixture by column chromatography (CC) in highly pure form in 15%–51.4% yield. Full article

(This article belongs to the Section Organic Chemistry)

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325 KiB

Open AccessArticle

Comprehensive Study of Honey with Protected Denomination of Origin and Contribution to the Enhancement of Legal Specifications

by Antonio Iglesias, Xesus Feás, Sandra Rodrigues, Julio A. Seijas, M. Pilar Vázquez-Tato, Luís G. Dias and Leticia M. Estevinho

Molecules 2012, 17(7), 8561-8577; https://doi.org/10.3390/molecules17078561 - 17 Jul 2012

Cited by 42 | Viewed by 7627

Abstract

In this study the characterization of a total of 60 honey samples with Protected Denomination of Origin (PDO) collected over three harvests (2009–2011, inclusive), from the Northeast of Portugal was carried out based on the presence of pollen, physicochemical and microbiological characteristics. All [...] Read more.

In this study the characterization of a total of 60 honey samples with Protected Denomination of Origin (PDO) collected over three harvests (2009–2011, inclusive), from the Northeast of Portugal was carried out based on the presence of pollen, physicochemical and microbiological characteristics. All samples were found to meet the European Legislation, but some didn’t meet the requirements of the PDO specifications. Concerning the floral origin of honey, our results showed the prevalence of rosemary (Lavandula pedunculata) pollen. The microbiological quality of all the analyzed samples was satisfactory, since fecal coliforms, sulfite-reducing clostridia and Salmonella were absent, and molds and yeasts were detected in low counts. Significant differences between the results were studied using one-way analysis of variance (ANOVA), followed by Tukey’s HSD test. The samples were submitted to discriminant function analysis, in order to determine which variables differentiate between two or more naturally occurring groups (Forward Stepwise Analysis). The variables selected were in this order: diastase activity, pH, reducing sugars, free acidity and HMF. The pollen spectrum has perfect discriminatory power. This is the first study in which a honey with PDO was tested, in order to assess its compliance with the PDO book of specifications. Full article

(This article belongs to the Section Natural Products Chemistry)

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198 KiB

Open AccessArticle

Two New Oxysporone Derivatives from the Fermentation Broth of the Endophytic Plant Fungus Pestalotiopsis karstenii Isolated from Stems of Camellia sasanqua

by Du Qiang Luo, Lei Zhang, Bao Zhong Shi and Xiao Mei Song

Molecules 2012, 17(7), 8554-8560; https://doi.org/10.3390/molecules17078554 - 17 Jul 2012

Cited by 23 | Viewed by 5120

Abstract

Two new oxysporone derivatives, pestalrone A (1) and pestalrone B (2), along with two known structurally related compounds 3,4, were from the fermentation broth of the endophytic plant fungus Pestalotiopsis karstenii isolated from stems of Camellia [...] Read more.

Two new oxysporone derivatives, pestalrone A (1) and pestalrone B (2), along with two known structurally related compounds 3,4, were from the fermentation broth of the endophytic plant fungus Pestalotiopsis karstenii isolated from stems of Camellia sasanqua. Their structures and relative configurations were elucidated by extensive spectroscopic analysis and comparison of chemical shifts with related known compounds. Compound 2 exhibited significant activities agains HeLa, HepG2 and U-251 with IC₅₀ values of 12.6, 31.7 and 5.4 µg/mL, respectively. Full article

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442 KiB

Open AccessArticle

Reactivity of Ruthenium Vinylidene Complexes Containing Indenyl/dppe Ligands and Unsaturated Bonds at Cd with Trimethylsilyl Azide

by Hui-Ling Sung, Tze-Min Her, Wen-Hsien Su and Chin-Pao Cheng

Molecules 2012, 17(7), 8533-8553; https://doi.org/10.3390/molecules17078533 - 17 Jul 2012

Cited by 7 | Viewed by 5765

Abstract

This study presents a new reaction of cationic vinylidene complexes with Me₃SiN₃ (TMSN₃), which yields N-coordinated nitrile complexes 3. Treatment of a ruthenium acetylide precursor containing indenyl and dppe ligands with a series of organic halides [...] Read more.

This study presents a new reaction of cationic vinylidene complexes with Me₃SiN₃ (TMSN₃), which yields N-coordinated nitrile complexes 3. Treatment of a ruthenium acetylide precursor containing indenyl and dppe ligands with a series of organic halides produced the corresponding vinylidene complexes 2 in good yield. Further reaction of 2 with TMSN₃ at room temperature produced N-coordinated ruthenium nitrile complexes 3. Unlike the reaction of cyclopropenylruthenium complexes with TMSN₃, which yielded different products depending on the substituent at Cγ, the vinylidene complexes containing unsaturated bonds at Cd yielded similar N-coordinated nitrile complexes. This transformation did not seemingly occur in the reaction of ruthenium vinylidene complexes containing Cp and PPh₃ ligands with TMSN₃. Deprotonation of these vinylidene complexes yielded cyclopropenyl or thermodynamic furylruthenium complexes, depending on the substitute at Cγ. Subsequent reactions of the cyclopropenyl or furylruthenium complexes with TMSN₃ afforded different products. Full article

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Open AccessArticle

Preparation and Preliminary Biological Evaluation of Novel ^99mTc-Labelled Thymidine Analogs as Tumor Imaging Agents

by Chunxiong Lu, Quanfu Jiang, Cheng Tan, Jie Tang and Jiankang Zhang

Molecules 2012, 17(7), 8518-8532; https://doi.org/10.3390/molecules17078518 - 16 Jul 2012

Cited by 6 | Viewed by 4387

Abstract

Two kinds of novel thymidine derivatives, N-thymidine-yl-N′-methyl-N′-{N′′-[2-sulfanyl-(ethylamino)acetyl]-2-aminoethylsulfanyl-1-hexanamide}-ethanediamine (TMHEA) and N-thymidine-yl-N′-methyl-N′-{N′′-[2-sulfanyl-(ethylamino)acetyl]-2-aminoethylsulfanyl-1-hexanamide}-hexanediamine (TMHHA) were prepared and successfully labeled with ^99mTc in high labeling yields. The in vitro stability and in [...] Read more.

Two kinds of novel thymidine derivatives, N-thymidine-yl-N′-methyl-N′-{N′′-[2-sulfanyl-(ethylamino)acetyl]-2-aminoethylsulfanyl-1-hexanamide}-ethanediamine (TMHEA) and N-thymidine-yl-N′-methyl-N′-{N′′-[2-sulfanyl-(ethylamino)acetyl]-2-aminoethylsulfanyl-1-hexanamide}-hexanediamine (TMHHA) were prepared and successfully labeled with ^99mTc in high labeling yields. The in vitro stability and in vivo biodistribution of ^99mTc-TMHEA and ^99mTc-TMHHA were investigated and compared. The biodistribution studies indicate that the radiotracer ^99mTc-TMHEA displays selective tumor uptake, suggesting it is a potential tumor imaging agent. Full article

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Open AccessArticle

Green Biosynthesis of Silver Nanoparticles Using Callicarpa maingayi Stem Bark Extraction

by Kamyar Shameli, Mansor Bin Ahmad, Emad A. Jaffar Al-Mulla, Nor Azowa Ibrahim, Parvaneh Shabanzadeh, Abdolhossein Rustaiyan, Yadollah Abdollahi, Samira Bagheri, Sanaz Abdolmohammadi, Muhammad Sani Usman and Mohammed Zidan

Molecules 2012, 17(7), 8506-8517; https://doi.org/10.3390/molecules17078506 - 16 Jul 2012

Cited by 221 | Viewed by 11888

Abstract

Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs) due to their multiple applications. The use of plants in the green synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the green biosynthesis of [...] Read more.

Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs) due to their multiple applications. The use of plants in the green synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the green biosynthesis of silver nanoparticles using Callicarpa maingayi stem bark extract has been reported. Characterizations of nanoparticles were done using different methods, which include; ultraviolet-visible spectroscopy (UV-Vis), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDXF) spectrometry, zeta potential measurements and Fourier transform infrared (FT-IR) spectroscopy. UV-visible spectrum of the aqueous medium containing silver nanoparticles showed absorption peak at around 456 nm. The TEM study showed that mean diameter and standard deviation for the formation of silver nanoparticles were 12.40 ± 3.27 nm. The XRD study showed that the particles are crystalline in nature, with a face centered cubic (fcc) structure. The most needed outcome of this work will be the development of value added products from Callicarpa maingayi for biomedical and nanotechnology based industries. Full article

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Open AccessArticle

Influence of ShuJinHuoXue Tablets on Ischemia Reperfusion Injury of Animals’ Skeletal Muscle

by Zhihong Tong, Fang Yu, Zhonghua Liu and Haidong Liang

Molecules 2012, 17(7), 8494-8505; https://doi.org/10.3390/molecules17078494 - 16 Jul 2012

Cited by 12 | Viewed by 4698

Abstract

Ischemia-reperfusion (IR) can lead to serious tissue oxidative injury in animals. ShuJinHuoXue tablet (SJHXT) is a Chinese Traditional Medicine which can relax the muscles and stimulate the blood circulation and has been used as a clinical medicine. In the present study, we investigated [...] Read more.

Ischemia-reperfusion (IR) can lead to serious tissue oxidative injury in animals. ShuJinHuoXue tablet (SJHXT) is a Chinese Traditional Medicine which can relax the muscles and stimulate the blood circulation and has been used as a clinical medicine. In the present study, we investigated the effects of SJHXT pretreatment on oxidative injury using an animal model of acute limb IR. Results showed that SJHXT pre-treatment (200, 300 and 400 mg/kg/day) markedly reduced serum endothelin-1 (ET-1), thromboxane B2 (TXB₂) levels and thromboxane B2/6-keto- prostaglandin F1α (TXB₂/6-Keto-PGF_1α), wet weight/dried weight (W/D) ratio, myeloperoxidase (MPO), creatine kinase (CK), lactate dehydrogenase (LDH) activities, and increased serum nitric oxide (NO), 6-Keto-PGF_1α levels and NO/ET-1 ratio in the IR+SJHXT groups. In addition, the SJHXT pre-treatment (200, 300 and 400 mg/kg/day) markedly reduced skeletal muscle Ca²⁺, malondialdehyde (MDA) levels, increased Na⁺-K⁺-ATPase, Ca²⁺-Mg²⁺-ATPase, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities. Our results suggest that SJHXT pre-treatment may improve skeletal muscle blood vessel microcirculation, decrease skeletal muscle oxidative injury and enhance antioxidant enzymes activities in IR animals. Full article

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Open AccessArticle

Synthesis, Tautomeric Structure and Antimicrobial Activity of 3-Arylhydrazono-4-phenyl-[1,2,4]-triazepino[2,3-a]quinazoline-2,7(1H)-diones

by Thoraya Abdel Reheem Farghaly, Mastoura Mohamed Edrees and Mosselhi Abdelnabi Mosselhi

Molecules 2012, 17(7), 8483-8493; https://doi.org/10.3390/molecules17078483 - 13 Jul 2012

Cited by 8 | Viewed by 5054

Abstract

A simple strategy for the synthesis of the hitherto unreported 3-arylazo-4-phenyl- [1,2,4]triazepino[2,3-a]quinazoline-2,7(1H)-diones is described. Spectral data indicated that the studied compounds exist predominantly in the hydrazone tautomeric form. The antimicrobial activity of the newly synthesized compounds was also evaluated. [...] Read more.

A simple strategy for the synthesis of the hitherto unreported 3-arylazo-4-phenyl- [1,2,4]triazepino[2,3-a]quinazoline-2,7(1H)-diones is described. Spectral data indicated that the studied compounds exist predominantly in the hydrazone tautomeric form. The antimicrobial activity of the newly synthesized compounds was also evaluated. The results indicated that some of these compounds have moderate activity towards bacteria. Full article

(This article belongs to the Section Organic Chemistry)

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Open AccessArticle

Antimycobacterial Activity of Constituents from Foeniculum vulgare Var. Dulce Grown in Mexico

by Patricia C. Esquivel-Ferriño, Juan Manuel J. Favela-Hernández, Elvira Garza-González, Noemí Waksman, María Yolanda Ríos and María del Rayo Camacho-Corona

Molecules 2012, 17(7), 8471-8482; https://doi.org/10.3390/molecules17078471 - 13 Jul 2012

Cited by 61 | Viewed by 7308

Abstract

Bioassay guided fractionation of an antimycobacterial extract of Foeniculum vulgare var dulce (Apiaceae) led to the isolation and characterization of 5-hydroxyfurano-coumarin. The chemical structure of this compound was elucidated by ¹H and ¹³C (1D and 2D) Nuclear Magnetic Resonance (NMR) spectroscopy. [...] Read more.

Bioassay guided fractionation of an antimycobacterial extract of Foeniculum vulgare var dulce (Apiaceae) led to the isolation and characterization of 5-hydroxyfurano-coumarin. The chemical structure of this compound was elucidated by ¹H and ¹³C (1D and 2D) Nuclear Magnetic Resonance (NMR) spectroscopy. In addition, the active fractions were analyzed by GC-MS and seventy eight compounds were identified; the major compounds were 1,3-benzenediol, 1-methoxycyclohexene, o-cymene, sorbic acid, 2-hydroxy-3-methyl-2-cyclopenten-1-one, estragole, limonene-10-ol and 3-methyl-2-cyclopenten-1-one. Twenty compounds identified in the active fractions were tested against one sensitive and three MDR strains of Mycobacterium tuberculosis using the Alamar Blue microassay. Compounds that showed some degree of antimycobacterial activity against all strains tested were the following: linoleic acid (MIC 100 µg/mL), oleic acid (MIC 100 µg/mL), 1,3-benzenediol (MIC 100–200 µg/mL), undecanal (MIC 50–200 µg/mL), and 2,4-undecadienal (MIC 25–50 µg/mL), the last being the most active compound. To our knowledge, this is the first report of the presence of 5-hydroxy-furanocoumarin in F. vulgare. Full article

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Open AccessArticle

Enzymatic Reduction of 9-Methoxytariacuripyrone by Saccharomyces cerevisiae and Its Antimycobacterial Activity

by Patricia Alvarez-Fitz, Laura Alvarez, Silvia Marquina, Julieta Luna-Herrera and Víctor Manuel Navarro-García

Molecules 2012, 17(7), 8464-8470; https://doi.org/10.3390/molecules17078464 - 12 Jul 2012

Cited by 11 | Viewed by 5149

Abstract

Biotransformation processes have been successfully utilized to obtain products of pharmaceutical, chemical, food, and agricultural interest, which are difficult to obtain by classic chemical methods. The compound with antituberculous activity, 9-methoxy-tariacuripyrone (1), isolated from Aristolochia brevipes, was submitted to biotransformation [...] Read more.

Biotransformation processes have been successfully utilized to obtain products of pharmaceutical, chemical, food, and agricultural interest, which are difficult to obtain by classic chemical methods. The compound with antituberculous activity, 9-methoxy-tariacuripyrone (1), isolated from Aristolochia brevipes, was submitted to biotransformation with the yeast Saccharomyces cerevisiae under culture, yielding 5-amino-9-methoxy-3,4-dihydro-2H-benzo[h]chromen-2-one (2). The structure of 2 was elucidated on the basis of spectroscopic analyses. The results mainly show the reduction of the double bond and the nitro group of compound 1. Metabolite 2 demonstrated an increase in anti-tuberculous activity (MIC = 3.12 µg/mL) against the drug-sensitive Mycobacterium tuberculosis (H37Rv) strain, with respect to that shown by 1. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Uses of Cyanoacetylhydrazine in Heterocyclic Synthesis: Novel Synthesis of Pyrazole Derivatives with Anti-tumor Activities

by Rafat M. Mohareb, Nahed N. E. El-Sayed and Mahmoud A. Abdelaziz

Molecules 2012, 17(7), 8449-8463; https://doi.org/10.3390/molecules17078449 - 12 Jul 2012

Cited by 37 | Viewed by 6258

Abstract

The reaction of cyanoacetylhydrazine with chloroacetyl chloride gave N'-(2-chloroacetyl)-2-cyanoacetohydrazide. The latter underwent cyclization to afford 1-(5 amino-3-hydroxy-1H-pyrazol-1-yl)-2-chloroethanone, which underwent nucleophilic substitution to give 3-(5-amino-3-hydroxy-1H-pyrazol-1-yl)-3-oxopropanenitrile. The latter two compounds were used as key synthons to synthesize new thiophene, pyran, thiazole and [...] Read more.

The reaction of cyanoacetylhydrazine with chloroacetyl chloride gave N'-(2-chloroacetyl)-2-cyanoacetohydrazide. The latter underwent cyclization to afford 1-(5 amino-3-hydroxy-1H-pyrazol-1-yl)-2-chloroethanone, which underwent nucleophilic substitution to give 3-(5-amino-3-hydroxy-1H-pyrazol-1-yl)-3-oxopropanenitrile. The latter two compounds were used as key synthons to synthesize new thiophene, pyran, thiazole and some fused heterocyclic derivatives. The antitumor activity of the newly synthesized compounds was evaluated against three human tumor cells lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) and some of these compounds were found to exhibit much higher inhibitory effects towards the three tumor cell lines than the Gram positive control doxorubicin. Full article

(This article belongs to the Section Medicinal Chemistry)

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Open AccessArticle

Antifungal Activity, Toxicity and Chemical Composition of the Essential Oil of Coriandrum sativum L. Fruits

by Bruna V. Soares, Selene M. Morais, Raquel Oliveira Dos Santos Fontenelle, Vanessa A. Queiroz, Nadja S. Vila-Nova, Christiana M. C. Pereira, Edy S. Brito, Manoel A. S. Neto, Erika H. S. Brito, Carolina S. P. Cavalcante, Débora S. C. M. Castelo-Branco and Marcos F. G. Rocha

Molecules 2012, 17(7), 8439-8448; https://doi.org/10.3390/molecules17078439 - 11 Jul 2012

Cited by 54 | Viewed by 7951

Abstract

The aims of this study were to test the antifungal activity, toxicity and chemical composition of essential oil from C. sativum L. fruits. The essential oil, obtained by hydro-distillation, was analyzed by gas chromatography/mass spectroscopy. Linalool was the main constituent (58.22%). The oil [...] Read more.

The aims of this study were to test the antifungal activity, toxicity and chemical composition of essential oil from C. sativum L. fruits. The essential oil, obtained by hydro-distillation, was analyzed by gas chromatography/mass spectroscopy. Linalool was the main constituent (58.22%). The oil was considered bioactive, showing an LC₅₀ value of 23 µg/mL in the Artemia salina lethality test. The antifungal activity was evaluated against Microsporum canis and Candida spp. by the agar-well diffusion method and the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) were established by the broth microdilution method. The essential oil induced growth inhibition zones of 28 ± 5.42 and 9.25 ± 0.5 for M. canis and Candida spp. respectively. The MICs and MFCs for M. canis strains ranged from 78 to 620 and 150 to 1,250 µg/mL, and the MICs and MFCs for Candida spp strains ranged from 310 to 620 and 620 to 1,250 µg/mL, respectively. C. sativum essential oil is active in vitro against M. canis and Candida spp. demonstrating good antifungal activity. Full article

(This article belongs to the Collection Bioactive Compounds)

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Open AccessArticle

Aqueous Synthesis and Characterization of TGA-capped CdSe Quantum Dots at Freezing Temperature

by Qizhuang Sun, Shasha Fu, Tingmei Dong, Shuxian Liu and Chaobiao Huang

Molecules 2012, 17(7), 8430-8438; https://doi.org/10.3390/molecules17078430 - 11 Jul 2012

Cited by 36 | Viewed by 5944

Abstract

CdSe quantum dots (QDs) have traditionally been synthesized in organic phase and then transferred to aqueous solution by functionalizing their surface with silica, polymers, short-chain thiol ligands, or phospholipid micelles. However, a drastic increase in the hydrodynamic size and biotoxicity of QDs may [...] Read more.

CdSe quantum dots (QDs) have traditionally been synthesized in organic phase and then transferred to aqueous solution by functionalizing their surface with silica, polymers, short-chain thiol ligands, or phospholipid micelles. However, a drastic increase in the hydrodynamic size and biotoxicity of QDs may hinder their biomedical applications. In this paper, the TGA-capped CdSe QDs are directly synthesized in aqueous phase at freezing temperature, and they prove to possess high QY (up to 14%). Full article

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Open AccessArticle

Evaluation of Antioxidant and Immunity-Enhancing Activities of Sargassum pallidum Aqueous Extract in Gastric Cancer Rats

by Rui-Li Zhang, Wen-Da Luo, Tie-Nan Bi and Shen-Kang Zhou

Molecules 2012, 17(7), 8419-8429; https://doi.org/10.3390/molecules17078419 - 11 Jul 2012

Cited by 35 | Viewed by 6471

Abstract

The effect of Sargassum pallidum (brown seaweed) aqueous extract on the immunity function and antioxidant activities in was studied gastric cancer rats. Treatment with Sargassum pallidum aqueous extract at oral doses 400, 600 or 800 mg/kg body weight was found to provide a [...] Read more.

The effect of Sargassum pallidum (brown seaweed) aqueous extract on the immunity function and antioxidant activities in was studied gastric cancer rats. Treatment with Sargassum pallidum aqueous extract at oral doses 400, 600 or 800 mg/kg body weight was found to provide a dose-dependent protection against N-methyl-N′-nitro-N-nitrosoguanidine (MNNG)-induced immunity damage and oxidative injury by enhancing serum interleukin-2 (IL-2), interleukin-4 (IL-4), interleukin-10 (IL-10) levels, decreasing interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α) levels, preserving normal antioxidant enzymes activities, and by inhibiting lipid peroxidation in gastric mucosa. It can be concluded that Sargassum pallidum aqueous extract may enhance the immunity and antioxidant activities in gastric cancer rats. Full article

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Open AccessArticle

Effect of Gender, Season, and Vitamin D Status on Bone Biochemical Markers in Saudi Diabetes Patients

by Nasser M. Al-Daghri, Khalid M. Alkharfy, Abdulaziz Al-Othman, Sobhy M. Yakout, Yousef Al-Saleh, Mona A. Fouda, Riad Sulimani and Shaun Sabico

Molecules 2012, 17(7), 8408-8418; https://doi.org/10.3390/molecules17078408 - 11 Jul 2012

Cited by 7 | Viewed by 5243

Abstract

Biochemical bone turnover markers (BTMs) provide important information on the diagnosis, therapy and monitoring of metabolic bone diseases. They are evident before measurable changes in bone mineral density (BMD) take place. A total of 35 adult Saudi patients (23 males; 12 females) with [...] Read more.

Biochemical bone turnover markers (BTMs) provide important information on the diagnosis, therapy and monitoring of metabolic bone diseases. They are evident before measurable changes in bone mineral density (BMD) take place. A total of 35 adult Saudi patients (23 males; 12 females) with type 2 diabetes and diagnosed to be vitamin D deficient were recruited in this prospective study. Here we investigated the effects of gender, season, and vitamin D status on bone biochemical markers of bone remodeling. Anthropometry and blood samples were collected at different intervals. Metabolic parameters and bone biomarkers were measured routinely and by ELISA. Both males and females had a significant increase in their vitamin D status over time, but no significant changes in the bone biomarkers were observed in females. In males there was a significant increase in circulating levels of corrected calcium and OPN (p = 0.004 and 0.01 respectively) and a significant decrease in crosslaps (p = 0.005). In all subjects there was a modest but significant positive relationship between vitamin D status and OC (R = 0.34; p = 0.04). In conclusion, our study demonstrates that changes in bone remodeling markers are affected by season, gender, and possibly vitamin D status. This gender difference may well reflect the physiologic pathway responsible for the higher peak bone mass achieved in males compared to females. Full article

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Open AccessArticle

Supercritical Extraction of Lycopene from Tomato Industrial Wastes with Ethane

by Beatriz P. Nobre, Luisa Gouveia, Patricia G. S. Matos, Ana F. Cristino, António F. Palavra and Rui L. Mendes

Molecules 2012, 17(7), 8397-8407; https://doi.org/10.3390/molecules17078397 - 11 Jul 2012

Cited by 28 | Viewed by 6900

Abstract

Supercritical fluid extraction of all-E-lycopene from tomato industrial wastes (mixture of skins and seeds) was carried out in a semi-continuous flow apparatus using ethane as supercritical solvent. The effect of pressure, temperature, feed particle size, solvent superficial velocity and matrix initial [...] Read more.

Supercritical fluid extraction of all-E-lycopene from tomato industrial wastes (mixture of skins and seeds) was carried out in a semi-continuous flow apparatus using ethane as supercritical solvent. The effect of pressure, temperature, feed particle size, solvent superficial velocity and matrix initial composition was evaluated. Moreover, the yield of the extraction was compared with that obtained with other supercritical solvents (supercritical CO₂ and a near critical mixture of ethane and propane). The recovery of all-E-lycopene increased with pressure, decreased with the increase of the particle size in the initial stages of the extraction and was not practically affected by the solvent superficial velocity. The effect of the temperature was more complex. When the temperature increased from 40 to 60 °C the recovery of all-E-lycopene increased from 80 to 90%. However, for a further increase to 80 °C, the recovery remained almost the same, indicating that some E-Z isomerization could have occurred, as well as some degradation of lycopene. The recovery of all-E-lycopene was almost the same for feed samples with different all-E-lycopene content. Furthermore, when a batch with a higher all-E-lycopene content was used, supercritical ethane and a near critical mixture of ethane and propane showed to be better solvents than supercritical CO₂leading to a faster extraction with a higher recovery of the carotenoid. Full article

(This article belongs to the Special Issue Synthesis and Extraction in Supercritical Fluids)

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Synthesis of New 1,3,4-Thiadiazole and 1,2,3,4-Oxathiadiazole Derivatives from Carbohydrate Precursors and Study of Their Effect on Tyrosinase Enzyme

by Mohamed M. El-Sadek, Seham Y. Hassan, Huda E. Abdelwahab and Galila A. Yacout

Molecules 2012, 17(7), 8378-8396; https://doi.org/10.3390/molecules17078378 - 11 Jul 2012

Cited by 15 | Viewed by 5195

Abstract

5-(1,2,3,4-Tetrahydroxybutyl)-2-methylfuran-3-carbohydrazide (2) was condensed with a variety of ketones to afford carbohydrazide derivatives 3–6. Acetylation of 3–5 afforded the acetyl derivatives 7–9, while periodate oxidation of 3–6 afforded the formyl derivatives [...] Read more.

5-(1,2,3,4-Tetrahydroxybutyl)-2-methylfuran-3-carbohydrazide (2) was condensed with a variety of ketones to afford carbohydrazide derivatives 3–6. Acetylation of 3–5 afforded the acetyl derivatives 7–9, while periodate oxidation of 3–6 afforded the formyl derivatives 10–13. Acid catalyzed condensation of thiosemicarbazide or o-tolylthiosemicarbazide with the prepared aldehydes 10–12 gave thiosemicarbazone derivatives 14–19. Cyclization of the latter with acetic anhydride afforded 4,5-dihydro-1,3,4-thiadiazolyl derivatives 20–25. On the other hand, condensation of p-tosylhydrazine with the prepared aldehydes 10–12 afforded p-tosylhydrazone derivatives 26–28. Cyclization of 26–28 with acetic anhydride afforded 1,2,3,4-oxathiadiazole derivatives 29–31 respectively. Moreover, the obtained results regarding to the effect of some of the prepared compounds on tyrosinase enzyme showed that the majority of these compounds having an inhibitory effect; especially compounds 12, 16, 17, and 28. Full article

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Open AccessArticle

Organic Bee Pollen: Botanical Origin, Nutritional Value, Bioactive Compounds, Antioxidant Activity and Microbiological Quality

by Xesús Feás, M. Pilar Vázquez-Tato, Leticia Estevinho, Julio A. Seijas and Antonio Iglesias

Molecules 2012, 17(7), 8359-8377; https://doi.org/10.3390/molecules17078359 - 11 Jul 2012

Cited by 221 | Viewed by 14826

Abstract

Organic bee pollen (BP, n = 22) harvested from the Douro International Natural Park (DINP, Portugal) was studied. Nine botanical families were found in the mixture of the samples. The water activity and pH ranged 0.21–0.37 and 4.3–5.2, respectively. The BP analyses averaged [...] Read more.

Organic bee pollen (BP, n = 22) harvested from the Douro International Natural Park (DINP, Portugal) was studied. Nine botanical families were found in the mixture of the samples. The water activity and pH ranged 0.21–0.37 and 4.3–5.2, respectively. The BP analyses averaged 67.7% carbohydrates, 21.8% crude protein, 5.2% crude fat and 2.9% ash. The energy ranged from 396.4 to 411.1 kcal/100 g. The principal fatty acid found was linolenic, followed by linoleic acid, palmitic acid and oleic acid. The phenolic and flavonoid contents varied from 12.9 to 19.8 mg of gallic acid equivalents/g of extract and from 4.5 to 7.1 mg of catechin equivalents/g of extract, respectively. The scavenger activity and β-carotene bleaching assays values (EC₅₀) were 3.0 ± 0.7 mg/mL and 4.6 mg/mL ± 0.9 mg/mL, respectively. E. coli, sulphite-reducing Clostridia, Salmonella and S. aureus were not found. Since there are studies indicating appreciable differences among BPs from different regions, the full characterization of BP from diverse origins still appears to be a sound research priority in order to obtain reliable data about this beehive product. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessCommunication

Electrospray Ionization Mass Spectrometric Analysis of Highly Reactive Glycosyl Halides

by Attila Bokros, Annamária Bánfi, Zoltán Kupihár, Zoltán Kele, Tünde Zita Illyés, János Szolomájer and Lajos Kovács

Molecules 2012, 17(7), 8351-8358; https://doi.org/10.3390/molecules17078351 - 10 Jul 2012

Cited by 2 | Viewed by 5557

Abstract

Highly reactive glycosyl chlorides and bromides have been analysed by a routine mass spectrometric method using electrospray ionization and lithium salt adduct-forming agents in anhydrous acetonitrile solution, providing salient lithiated molecular ions [M+Li]⁺, [2M+Li]⁺ etc. The role of other adduct-forming [...] Read more.

Highly reactive glycosyl chlorides and bromides have been analysed by a routine mass spectrometric method using electrospray ionization and lithium salt adduct-forming agents in anhydrous acetonitrile solution, providing salient lithiated molecular ions [M+Li]⁺, [2M+Li]⁺ etc. The role of other adduct-forming salts has also been evaluated. The lithium salt method is useful for accurate mass determination of these highly sensitive compounds. Full article

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Molecules, Volume 17, Issue 7 (July 2012) – 82 articles , Pages 7612-8734

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