We previously functionally characterized a novel marine microbial GDSL lipase MT6 and identified that the stereo-selectivity of MT6 was opposite to that of other common lipases in trans-esterification reactions.Herein...We previously functionally characterized a novel marine microbial GDSL lipase MT6 and identified that the stereo-selectivity of MT6 was opposite to that of other common lipases in trans-esterification reactions.Herein,we have investigated the use of MT6 in stereo-selective biocatalysis through direct hydrolysis reactions.Notably,the stereo-selectivity of MT6 was also demonstrated to be opposite to that of other common lipases in hydrolysis reactions.Parameters,including temperature,organic co-solvents,pH,ionic strength,catalyst loading,substrate concentration,and reaction time,affecting the enzymatic resolution of racemic 1-phenylethyl acetate were further investigated,with the e.e.of the final（S）-l-Phenylethanol product and the conversion being 97%and 28.5%,respectively,after process optimization.The lengths of side chains of 1-phenylethyl esters greatly affected the stereo-selectivity and conversion during kinetic resolutions.MT6 is a novel marine microbial GDSL lipase exhibiting opposite stereo-selectivities than other common lipases in both trans-esterification reactions and hydrolysis reactions.展开更多
AIM: To investigate the protective effect against two immune liver injury models in mice by 2-amino-2-[2-(4-octylphenyl) ethyl] propane-l,3-diol hydrochloride and its possible mechanisms in Con A-induced liver damage....AIM: To investigate the protective effect against two immune liver injury models in mice by 2-amino-2-[2-(4-octylphenyl) ethyl] propane-l,3-diol hydrochloride and its possible mechanisms in Con A-induced liver damage. METHODS: Liver tissue or hepatocyte injury was monitored biochemically by measuring alanine aminotransferase (sALT) and aspartate aminotransferase (sAST) activity. Hematoxylin & eosin (HE) staining was used for histopathological examination. To evaluate the role of IFN-γ and IL-4 in the liver injury, serum levels of IFN-γ and IL-4 were determined using commercially available ELISA kit at 12 h after Con A challenge. We also determined FTY 720-induced spleen cell apoptosis by flow cytometry analysis or spleen cell proliferation test. RESULTS: Different doses of FTY 720 treatment dramatically reduced circulating markers of hepatocyte injury in two kinds of immunological liver injury models. FTY 720 dramatically reduced the elevated serum IFN-γ and IL-4 levels after Con A injection. Effect of spleen cell supernatants treated with Con A or FTY 720 on hepatocytes showed that ALT activities in cultured hepatocyte supernatants in Con A treatment group increased markedly and FTY 720 could reduce this elevated ALT activities in FTY 720 treatment group. FTY 720 dose-dependently increased the percentage of apoptotic cells in T cells and inhibited splenocyte proliferation induced by Con A. CONCLUSION: Pretreatment with FTY 720 was shown to produce protective effect on the immune liver injury in mice. The possible mechanism of FTY 720 on Con A-induced liver damage is that it could inhibit lymphocyte proliferation and induce lymphocyte apoptosis, resulting in the reduction of IL-4 or IFN-γ release, and subsequently protecting liver from being damaged by Con A.展开更多
(S)-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of (S)-3,5-bistrifluoromethylphenyl ethanol was successfully performed i...(S)-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of (S)-3,5-bistrifluoromethylphenyl ethanol was successfully performed in high enantiomeric excess (e.e.) through asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone catalyzed by Candida tropicalis 104 cells. The influence of some key reaction parameters such as substrate concentration, co-substrate and its concentration, biomass and reaction time was examined, respectively. The results showed that these factors obviously influence the yield, but the optical purity of the prepared product remains intact. The opti-mum conditions for the preparation of (S)-3,5-bistrifluoromethylphenyl ethanol were found to be as follows: sub-strate concentration 50 mmol?L?1; 50 g·L-1 of maltose as co-substrate; wet cell concentration 300 g·L-1; reaction for 30 h. Under above optimal conditions, the maximum yield for (S)-3,5-bistrifluoromethylphenyl ethanol reached 70.3% with 100% of product e.e.展开更多
In the present work we investigated, for the first time, the anti-inflammatory activity and the antioxidant properties of aqueous and ethanolic extracts, obtained from stem bark of Geoffroea decorticans （Gill. ex Hoo...In the present work we investigated, for the first time, the anti-inflammatory activity and the antioxidant properties of aqueous and ethanolic extracts, obtained from stem bark of Geoffroea decorticans （Gill. ex Hook. et Am.） Burk. （Fabaceae）. G. decorticans, commonly known as ＂chafiar＂ or ＂chafiarcillo＂, is a traditional argentinean plant used as emollient, balsamic, antitussive, expectorant and anti-inflammatory. The stem bark was collected from San Francisco del Monte de Oro, San Luis, Argentina. Anti-inflammatory activity was evaluated by carrageenan-induced paw edema in rats. Antioxidant activity was tested using 1,1-Diphenyl-2-picrylhydrazyl radical-scavenging activity （DPPH）, 2,2＂-Azino-bis（3-ethylbenzthiazoline-6-sulphonic acid） radical scavenging activity （ABTS） and ferric ion-reducing power （RP-Fe） assays. Aqueous extract 10% p/v showed anti-inflammatory activity （3h, 48% inhibition, 5h 37% inhibition and 7h 17% inhibition） and antioxidant activity （DPPH, ICs0 （mg/mL） = 0.098 =1： 0.032; ABTS, ICs0 （mg/mL） = 0.022 ~ 0.343, RP-Fe IC50 （mg/mL） = 1.124 ~ 0.146）. In the other hand, the ethanolic extract 5% p/v, presented anti-inflammatory activity （3h, 34% inhibition, 5h 38% inhibition and 7h 35% inhibition） and antioxidant activity （DPPH, IC50 （mg/mL） = 0.133 q- 0.027; ABTS, IC50 （mg/mL） = 0.086 ＋ 0.262, RP-Fe IC50 （mg/mL） = 7.089 ± 0.104）. These results suggest that, also fruits, the aqueous and ethanolic extracts from the stem bark of G. decorticans present significant anti-inflammatory activity and antioxidant properties.展开更多
Peptide nanofibers decorated with palladium nanoparticles catalyzed direct coupling of aryl halides with hydroxybenzotriazole to afford the corresponding biaryls in good to excellent yields.The coupling reactions proc...Peptide nanofibers decorated with palladium nanoparticles catalyzed direct coupling of aryl halides with hydroxybenzotriazole to afford the corresponding biaryls in good to excellent yields.The coupling reactions proceeded under simple,green,and mild conditions.The peptide nanofibers were used as recyclable supports in the coupling reactions.This approach is the first to use hydroxybenzotriazole as a phenylating agent.展开更多
The solid-phase synthesis of isoxazolines on 2-polystyrylsulfonamidoethanol resin is reported. 2-Polystyrylsulfonamidoethanol resin 1 was reacted with acryloyl chloride to afford 2-polystyrylsulfonylamidoethyl acrylat...The solid-phase synthesis of isoxazolines on 2-polystyrylsulfonamidoethanol resin is reported. 2-Polystyrylsulfonamidoethanol resin 1 was reacted with acryloyl chloride to afford 2-polystyrylsulfonylamidoethyl acrylate resin 2, which was further reacted with brominated aldoximes by [3+2] cycloaddition to give isoxazoline resin 4. Resin 4 was treated with aqueous 6 mol/L HCl solution to obtain isoxazolines in good yield and purity.展开更多
A series of segmented polyether-polyester polyurethane with amorphous hydrophilic soft segment domains were prepared from 4,4'- diphenylmethane diisocyanate (MDI), polybutylene adipate (Glycol) 2000 (PBA2000), and...A series of segmented polyether-polyester polyurethane with amorphous hydrophilic soft segment domains were prepared from 4,4'- diphenylmethane diisocyanate (MDI), polybutylene adipate (Glycol) 2000 (PBA2000), and polyethylene glycol 1000 (PEG1000), with 1,4-butanediol (BDO) as the chain extender. Furthermore, several representative properties of the polyurethanes, such as moisture permeability, water resistance, hydrophilic property, and phase inversion temperature, were investigated. The studies show that the structure and concentration of soft segment have a remarkable effect on the main application properties of polyurethane. On the contrary, the functional properties of the polyurethane are almost not affected by its hard segment.展开更多
The crystal structure of the title compound carvedilol, C24H25N2O4(Mr= 406. 47), has determined by single-crystal X-ray diffraction. The crystal is mono-clinic with space group P21/c, a=9. 094(l), b= l2. 754(1), c= 18...The crystal structure of the title compound carvedilol, C24H25N2O4(Mr= 406. 47), has determined by single-crystal X-ray diffraction. The crystal is mono-clinic with space group P21/c, a=9. 094(l), b= l2. 754(1), c= 18. 330(2) A, β=97. 36(1 )°, V= 2l08. 5(4) A 3, Z= 4, D.= l. 280 g/cm3, F(000) = 864, μ=O. O88mm-1 and final R= O. O368, wR(F2) = 0.0787 for reflections (I>2σ(I) ). X-ray anal-ysis reveals that the crystal is composed of a pair of enantiomer, and there are hydrogenbonds O(3) -H(3O) -N(l ) between the two enantimers. There are two planes in themolecule.展开更多
Herein reported is an example of one-dimensional coordination polymer [Co11(3,5-DBsq)2(dpg)]·(3,5-H2DBcat)2 (1) (3,5-DBsq = 3,5-di-tert-butylsemiquinonate, 3,5-H2DBcat = 3,5-di-tert-butyl-benzene-1,2-diol, dpg = ...Herein reported is an example of one-dimensional coordination polymer [Co11(3,5-DBsq)2(dpg)]·(3,5-H2DBcat)2 (1) (3,5-DBsq = 3,5-di-tert-butylsemiquinonate, 3,5-H2DBcat = 3,5-di-tert-butyl-benzene-1,2-diol, dpg = meso-alpha,beta-di(4-pyridyl)glycol) capable of undergoing thermal and photoinduced valence tautomeric transitions.展开更多
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA11030404),the Key Project from Chinese Academy of Sciences(KGZD-EW-606)the National Natural Science Foundation of China(21302199)Guangzhou Science and Technology Plan Projects(201510010012)
文摘We previously functionally characterized a novel marine microbial GDSL lipase MT6 and identified that the stereo-selectivity of MT6 was opposite to that of other common lipases in trans-esterification reactions.Herein,we have investigated the use of MT6 in stereo-selective biocatalysis through direct hydrolysis reactions.Notably,the stereo-selectivity of MT6 was also demonstrated to be opposite to that of other common lipases in hydrolysis reactions.Parameters,including temperature,organic co-solvents,pH,ionic strength,catalyst loading,substrate concentration,and reaction time,affecting the enzymatic resolution of racemic 1-phenylethyl acetate were further investigated,with the e.e.of the final（S）-l-Phenylethanol product and the conversion being 97%and 28.5%,respectively,after process optimization.The lengths of side chains of 1-phenylethyl esters greatly affected the stereo-selectivity and conversion during kinetic resolutions.MT6 is a novel marine microbial GDSL lipase exhibiting opposite stereo-selectivities than other common lipases in both trans-esterification reactions and hydrolysis reactions.
文摘AIM: To investigate the protective effect against two immune liver injury models in mice by 2-amino-2-[2-(4-octylphenyl) ethyl] propane-l,3-diol hydrochloride and its possible mechanisms in Con A-induced liver damage. METHODS: Liver tissue or hepatocyte injury was monitored biochemically by measuring alanine aminotransferase (sALT) and aspartate aminotransferase (sAST) activity. Hematoxylin & eosin (HE) staining was used for histopathological examination. To evaluate the role of IFN-γ and IL-4 in the liver injury, serum levels of IFN-γ and IL-4 were determined using commercially available ELISA kit at 12 h after Con A challenge. We also determined FTY 720-induced spleen cell apoptosis by flow cytometry analysis or spleen cell proliferation test. RESULTS: Different doses of FTY 720 treatment dramatically reduced circulating markers of hepatocyte injury in two kinds of immunological liver injury models. FTY 720 dramatically reduced the elevated serum IFN-γ and IL-4 levels after Con A injection. Effect of spleen cell supernatants treated with Con A or FTY 720 on hepatocytes showed that ALT activities in cultured hepatocyte supernatants in Con A treatment group increased markedly and FTY 720 could reduce this elevated ALT activities in FTY 720 treatment group. FTY 720 dose-dependently increased the percentage of apoptotic cells in T cells and inhibited splenocyte proliferation induced by Con A. CONCLUSION: Pretreatment with FTY 720 was shown to produce protective effect on the immune liver injury in mice. The possible mechanism of FTY 720 on Con A-induced liver damage is that it could inhibit lymphocyte proliferation and induce lymphocyte apoptosis, resulting in the reduction of IL-4 or IFN-γ release, and subsequently protecting liver from being damaged by Con A.
基金Supported by the National＇Natural Science Foundation of China （21076193） and Foundation of Zhejiang Key Developing Discipline of Pharmacy （20100609）.
文摘(S)-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of (S)-3,5-bistrifluoromethylphenyl ethanol was successfully performed in high enantiomeric excess (e.e.) through asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone catalyzed by Candida tropicalis 104 cells. The influence of some key reaction parameters such as substrate concentration, co-substrate and its concentration, biomass and reaction time was examined, respectively. The results showed that these factors obviously influence the yield, but the optical purity of the prepared product remains intact. The opti-mum conditions for the preparation of (S)-3,5-bistrifluoromethylphenyl ethanol were found to be as follows: sub-strate concentration 50 mmol?L?1; 50 g·L-1 of maltose as co-substrate; wet cell concentration 300 g·L-1; reaction for 30 h. Under above optimal conditions, the maximum yield for (S)-3,5-bistrifluoromethylphenyl ethanol reached 70.3% with 100% of product e.e.
文摘In the present work we investigated, for the first time, the anti-inflammatory activity and the antioxidant properties of aqueous and ethanolic extracts, obtained from stem bark of Geoffroea decorticans （Gill. ex Hook. et Am.） Burk. （Fabaceae）. G. decorticans, commonly known as ＂chafiar＂ or ＂chafiarcillo＂, is a traditional argentinean plant used as emollient, balsamic, antitussive, expectorant and anti-inflammatory. The stem bark was collected from San Francisco del Monte de Oro, San Luis, Argentina. Anti-inflammatory activity was evaluated by carrageenan-induced paw edema in rats. Antioxidant activity was tested using 1,1-Diphenyl-2-picrylhydrazyl radical-scavenging activity （DPPH）, 2,2＂-Azino-bis（3-ethylbenzthiazoline-6-sulphonic acid） radical scavenging activity （ABTS） and ferric ion-reducing power （RP-Fe） assays. Aqueous extract 10% p/v showed anti-inflammatory activity （3h, 48% inhibition, 5h 37% inhibition and 7h 17% inhibition） and antioxidant activity （DPPH, ICs0 （mg/mL） = 0.098 =1： 0.032; ABTS, ICs0 （mg/mL） = 0.022 ~ 0.343, RP-Fe IC50 （mg/mL） = 1.124 ~ 0.146）. In the other hand, the ethanolic extract 5% p/v, presented anti-inflammatory activity （3h, 34% inhibition, 5h 38% inhibition and 7h 35% inhibition） and antioxidant activity （DPPH, IC50 （mg/mL） = 0.133 q- 0.027; ABTS, IC50 （mg/mL） = 0.086 ＋ 0.262, RP-Fe IC50 （mg/mL） = 7.089 ± 0.104）. These results suggest that, also fruits, the aqueous and ethanolic extracts from the stem bark of G. decorticans present significant anti-inflammatory activity and antioxidant properties.
基金the Research Facility of Ilam University,Ilam,Iran,for financial support of this research project
文摘Peptide nanofibers decorated with palladium nanoparticles catalyzed direct coupling of aryl halides with hydroxybenzotriazole to afford the corresponding biaryls in good to excellent yields.The coupling reactions proceeded under simple,green,and mild conditions.The peptide nanofibers were used as recyclable supports in the coupling reactions.This approach is the first to use hydroxybenzotriazole as a phenylating agent.
基金NNSFC (20074017,29844001) and Visiting Scholar Foundation of Key Lab. In University
文摘The solid-phase synthesis of isoxazolines on 2-polystyrylsulfonamidoethanol resin is reported. 2-Polystyrylsulfonamidoethanol resin 1 was reacted with acryloyl chloride to afford 2-polystyrylsulfonylamidoethyl acrylate resin 2, which was further reacted with brominated aldoximes by [3+2] cycloaddition to give isoxazoline resin 4. Resin 4 was treated with aqueous 6 mol/L HCl solution to obtain isoxazolines in good yield and purity.
基金Key Foundation of Shannxi Province,China (No.04JK181)China Textile Industry Association(No.2007049)
文摘A series of segmented polyether-polyester polyurethane with amorphous hydrophilic soft segment domains were prepared from 4,4'- diphenylmethane diisocyanate (MDI), polybutylene adipate (Glycol) 2000 (PBA2000), and polyethylene glycol 1000 (PEG1000), with 1,4-butanediol (BDO) as the chain extender. Furthermore, several representative properties of the polyurethanes, such as moisture permeability, water resistance, hydrophilic property, and phase inversion temperature, were investigated. The studies show that the structure and concentration of soft segment have a remarkable effect on the main application properties of polyurethane. On the contrary, the functional properties of the polyurethane are almost not affected by its hard segment.
文摘The crystal structure of the title compound carvedilol, C24H25N2O4(Mr= 406. 47), has determined by single-crystal X-ray diffraction. The crystal is mono-clinic with space group P21/c, a=9. 094(l), b= l2. 754(1), c= 18. 330(2) A, β=97. 36(1 )°, V= 2l08. 5(4) A 3, Z= 4, D.= l. 280 g/cm3, F(000) = 864, μ=O. O88mm-1 and final R= O. O368, wR(F2) = 0.0787 for reflections (I>2σ(I) ). X-ray anal-ysis reveals that the crystal is composed of a pair of enantiomer, and there are hydrogenbonds O(3) -H(3O) -N(l ) between the two enantimers. There are two planes in themolecule.
基金financial support from the National Natural Science Foundation of China (90922012, 20971106 & 21021061)the Natural Science Foundation of Fujian Province for Distinguished Young Scientists (2009J06006)
文摘Herein reported is an example of one-dimensional coordination polymer [Co11(3,5-DBsq)2(dpg)]·(3,5-H2DBcat)2 (1) (3,5-DBsq = 3,5-di-tert-butylsemiquinonate, 3,5-H2DBcat = 3,5-di-tert-butyl-benzene-1,2-diol, dpg = meso-alpha,beta-di(4-pyridyl)glycol) capable of undergoing thermal and photoinduced valence tautomeric transitions.
