Trichosporon beigelli esterase (TBE): a versatile esterase for the resolution of economically important racemates
摘要:
A hydrolase producing strain Trichosporon beigelli esterase (TBE) isolated from local cottage cheese in its native form has displayed versatility and high efficacy in the kinetic resolution of a wide range of economically important substrates, which include racemic secondary alcohols, such as 1-(6-methoxy-2-naphtliyl)ethanol (E similar to 316), 1-(3,4-methylenedioxyphenyl)ethanol and pentanol (E similar to 180 and 156 resp.), and alkyl esters of carboxylic acids such as ibuprofen (E similar to 340), 2-(benzylthio)propanoic acid (E similar to 1000). In other substrates such as in the primary alcohol 2-(6-methoxy-2-naphthyl)propan-1-ol and carboxylic acids such as 2-(5-bromo-6-methoxy-2-naphthyl)propanoic acid, 2-(2-naphthyloxy)propanoic acid, and substituted 2-thiopropanoic acids, it displayed moderate to low selectivity. Commercial lipases such as CCL, PPL, and PSL were also used in the resolution of the substrates for comparative studies. (c) 2005 Elsevier Ltd. All rights reserved.
A New Method for Stereocontrolled Synthesis of Substituted Tetrahydrothiophenes
作者:Andrés Molina Ponce、Larry E. Overman
DOI:10.1021/ja001975m
日期:2000.9.1
A variety of substituted 3-acyltetrahydrothiophenes can be prepared with high stereoselectivity in 50−70% yield by acid-promoted condensation of mercapto allylic alcohols 1 (X = S) with aldehydes and ketones. The mercapto allylic alcohol must be substituted at the internal alkene carbon and the terminal alkene carbon must be unsubstituted. This newsynthesis of tetrahydrothiophenes will be most useful