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enzymatic synthesis of a CCK-8 Tripeptide Derivative

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Chinese Chemical Letters 2003年第2期14卷 167-168页

作者： Li GUO Zi Min LU 等 WestChinaSchoolofPharmacy SichuanUniversityChengdu610041 TongjiMedicalCollege HuazhongScience&TechnologyUniversityWuhan430030

The enzymatic synthesis of CCK-8 tripeptide derivative Phac-Met-Asp(OMe)-Phe-NH2 is reported. Starting with Phac-Met-OCam, we have successfully synthesized the target tripeptide with three free or immobilized enzymes, ?chymotrypsin, papain and thermolysin in reasonable yields. The key steps in this synthesis were the coupling of Phac-Met-OCam and H-Asp(OMe)2 to form Met-Asp peptide bond catalyzed by ?chymotrypsin and the selective hydrolysis of -ester of Phac-Met-Asp(OMe)2 catalyzed by papain.

关键词： enzymatic synthesis CCK-8 tripeptide derivative.

enzymatic synthesis of Dipeptide Derivatives Containing Non-coded Amino Acids in Organic Solvents

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Chinese Journal of Chemistry 2002年第11期20卷 1354-1357,1131页

作者：杨洪周闯田桂玲叶蕴华 Key Laboratory of Bio‐organic Chemistry and Molecular Engineering of Education Ministry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

A series of dipeptide derivatives containing non-coded amino acids, N-Boc-4-X-Phe-Ala-NHNHPh (X = Cl, Br, I, NO2), were synthesized by using thermoase in organic solvents. The physical data were consistent with the same samples prepared by 3-(diethoxyphosphoryloxy)-1, 2,3-benzotriazin-4 (3H)-one (DEPBT). Influence of different substituted groups of the noncoded amino acids and different organic solvents on the enzymatic peptide synthesis was studied.

关键词： thermoase DEPBT non-coded amino acid enzymatic synthesis peptide

enzymatic synthesis of Methyl-Galactoaldehyde

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Journal of Ocean University of Qingdao 2002年第2期1卷 145-147页

作者： WANGOun YUGuangli DivisionofMedicinalandNaturalProductsChemistry CollegeofPharmacyTheUniversityofIowaIA52242USA InstituteofMarineFoodandDrug OceanUniversityofQingdaoQingdao266003P.R.China

Methyl-galactosides were oxidized at room temperature by galactose oxidase in a one-step reaction and afforded methyl-galactoaldehyde in excellent yield and high purity. The resulting galactoaldehyde as a useful inter... 详细信息

关键词： methyl galactoside galactose oxidase enzymatic synthesis galactoaldehyde

enzymatic synthesis of isoquercitrin with naringinase under microwave irradiation

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Enzymatic synthesis of isoquercitrin with naringinase under ...

中国生物工程学会第六次全国会员代表大会暨第九届学术年会

作者：朱丹 Yi-yuan Mei Xiao-hui Xu Chuan-qi Jin Jin-xian Wu An Gong Jun Wang 江苏科技大学生物技术学院 School of Biotechnology Jiangsu University of Science and Technology Sericultural Research Institute Chinese Academy of Agricultural Sciences

Isoquercitrin,a key synthetic intermediate,has a wide range of biological activities,for the production of enzymatically modified isoquercitrin(EMIQ) which has received FDA safety ***,the synthesis of isoquercitrin is still problematic,requires a long reaction time,is unstable and easily oxidizes *** order to establish an efficient bioprocess for obtaining isoquercitrin,a biosynthesis of isoquercitrin using the naringinase-catalyzed hydrothermal synthesis of rutin under microwave irradiation was first carried *** has been proved the feasibility of the free enzyme under microwave *** irradiation can effectively strengthen the enzymatic reaction,reduce the activation *** also can change the enzyme microscopic configuration and the reaction *** catalytic effect has a great thrust on the promotion of the enzymatic reactions in industrial *** micro-technology may be applied to the effective synthesis of other precious ***,a bright future and a better effect would be achieved by unremitting *** this study,enzymatic reactions were performed in a microwave reactor for isoquercitrin *** volume ratio of enzyme solution,ionic liquid and rutin dissolved by buffer solution in the enzymatic synthesis of isoquercitrin reaction system was 180:720:*** reaction was initiated by adding naringinase and the mixtures at various substrate concentrations,enzyme concentrations,reaction time,microwave power and types of ionic *** microwave irradiation,the mixture sampled for every 10 min from the 30 min to the 70 *** crude hydrolysis products of rutin were determined and verificated by HPLC and *** yield was calculated as follows Eq.(1).Isoquercitrin yield(%)=moles of isoquercitrin/initial moles of rutin×100% (1)Reaction medium directly affects the reaction rate and the enzyme ***,ionic liquid has the strong ability of absorbing microwave,a

关键词： Microwave irradiation Naringinase Isoquercitrin enzymatic synthesis

enzymatic synthesis of Troxerutin Derivatives Containing Tetrahydroisoquinoline in Ionic Liquids

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Enzymatic Synthesis of Troxerutin Derivatives Containing Tet...

河南省化学会2018年学术年会

作者：李明肖咏梅毛璞杨亮茹袁金伟董振华屈凌波河南工业大学化学化工与环境学院河南省天然药物化学院士工作站

In recent years, many flavonoids have been used in pharmaceuticals, and they are prominent in anti cardiovascular disease, anti-inflammatory, anti liver disease, antibacterial, antioxidation.[1-3] Therefore, it has attracted wide attention of chemists and pharmacists. Herein, troxerutin derivatives containing tetrahydroisoquinoline were synthesized by enzyme-catalyzed approach in ionic liquids medium(Scheme 1). The effects of different ionic liquids, enzyme sources and water content on the reaction were also studied. The results showed that highest conversion yield(71.7%) was achieved using N-octylpyridinium bromide(OPyBr) in which water content lower than 1% as reaction medium catalyzed by Lipase LS-10.

关键词： enzymatic synthesis troxerutin derivatives troxerutin ionic liquid

enzymatic synthesis of troxerutin derivatives containing N-phenethylamine or N-benzylamine

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Enzymatic synthesis of troxerutin derivatives containing N-p...

河南省化学会2018年学术年会

作者：李明肖咏梅毛璞杨亮茹袁金伟董振华屈凌波河南工业大学化学化工与环境学院河南省天然药物化学院士工作站

Flavonoids are widely found in the nature as secondary metabolites of plants, and have extensive physiological, pharmacological activity and low toxicity.[1,2] The modification of flavonoids by enzymatic methods to improve their stabilities or modify their solubilities has attracted more attention.[3] In the biosynthesis field, amidation has been applied to the introduction of nitrogen containing groups. The study shows that the nitrogen containing groups are introduced into some flavonoids, and their biological activities have been greatly improved. In this experiment, troxerutin derivatives containing N-phenethylamine or N-benzylamine were synthesized catalyzed by enzyme(Scheme 1).

关键词： enzymatic synthesis nitrogen-containing troxerutin derivatives troxerutin

Efficient enzymatic synthesis of GDP-Sugars and Derivatives

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Efficient Enzymatic Synthesis of GDP-Sugars and Derivatives

中国化学会第29届学术年会

作者： Yonghui Liu Yun Xu Tianbang Song Peng Wang Wei Zhao State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy Nankai University

Carbohydrates are important lead compounds in drug discovery and disease curing. Chemical synthesis of carbohydrates has long steps and low yield, so more and more attention was devoted to enzymatic synthesis which has simple reaction. enzymatic synthesis of carbohydrates was mainly catalyzed by glycosyltransferases(GT) and Leloir stype GT are mainly used, sugar donor subtrates are sugar-nucleotides. Consequently, the preparation of sugar-nucleotides is very important for the enzymatic synthesis of bioactive oligosaccharides [1]. Recently, we found that NahK5697 could phosphorylate a number of monosaccharides including mannose and derivatives. Taking advantage of this and the promiscuity of NahK5697 and a GDP-Man pyrophosphorylase from Pyrococcus furiosus DSM3638(PFManC), we present an efficient one-pot three enzyme system for quick preparative-scale synthesis of GDP-sugars [2]. In order to provide more substrates for the study of glycosyltransferase, we synthesized here 14 analogs of mannose(Fig.1) to produce more non-natural sugar-nucleotide donors.

关键词： enzymatic synthesis Sugar-nucleotides Derivatives

Controllable Regioselective enzymatic synthesis of Methyl Shikimate Derivatives in Non-aqueous Media

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Controllable Regioselective Enzymatic Synthesis of Methyl Sh...

第五届全国化学生物学学术会议

作者：王娜李超汪海洋余孝其 Department of Chemistry Key Laboratory of Green Chemistry and Technology（Ministry of Education）Sichuan University Department of Chemistry Key Laboratory of Green Chemistry and Technology（Ministry of Education）Sichuan University Department of Chemistry Key Laboratory of Green Chemistry and Technology（Ministry of Education）Sichuan University Department of Chemistry Key Laboratory of Green Chemistry and Technology（Ministry of Education）Sichuan University

＜正＞Shikimic acid 1 is a key intermediate in the biosynthesis of aromatic amino acids（phenylalanine, tyrosine and tryptophan）as well as the folate *** it is a constituent of numerous natural products,some of which... 详细信息

关键词： enzymatic synthesis Methyl shikimate Regioselectivity

Two-step enzymatic selective synthesis,characterization,and in vitro evaluation of acyclovir-saccharide conjugates

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Two-step enzymatic selective synthesis,characterization,and ...

2009 International Conference of Natural Products and Traditional Medicine(ICNPTM’ 09)

作者： Bo Jiang Yan Zheng Jing Quan* Li-Min Zhu* College of Chemistry Chemical Engineering and Biotechnology Donghua University

Two novel acyclovir-saccharide conjugates were synthesized by an enzymatic selective method for the development of more effective prodrugs in inhibiting ***,transesterification of acyclovir with divinyl adipate were performed under the catalysis of Candida antarctica lipase acrylic resin in anhydrous acetone at 50 *** glucose and galactose were selected for synthesis acyclovirsaccharide conjugates with protease-catalyzed high regioselective *** structures of compounds were confirmed by the nuclear magnetic resonance（NMR）.In order to optimize the reaction yield,we investigated the influence factors of this trasesterificaion *** in vitro cytotoxic activity and anti-HBV activity were evaluated which measured in HepG2.2.15 *** results showed that acyclovir-saccharide conjugates are clearly less cytotoxic than the parent drug,and which of the two derivatives had no excessively ***,acyclovir-saccharide conjugates were more effective than acvclovir for both antiHBsAg and HBeAg,especially acyclovir-galactose *** data of SI show that acyclovir-saccharide conjugates are much more selective than the parent drug for HBV.

关键词： acyclovir-monosaccharide conjugates enzymatic synthesis anti-HBV activity