Microbial-catalysed resolution of sterically demanding cyanohydrins
摘要:
Mycelia containing carboxyl-esterases, a novel source of enzymes, have been investigated in the hydrolytic kinetic resolution of one type of tert-alcohols, alpha,alpha-disubstituted cyanohydrins. This class of enzymes Was found to be both active and selective towards these tert-alcohols, giving E-values as high as 42. (C) 2009 Elsevier B.V. All rights reserved.
An Enzymatic Toolbox for the Kinetic Resolution of 2-(Pyridin-x-yl)but-3-yn-2-ols and Tertiary Cyanohydrins
作者:Giang-Son Nguyen、Robert Kourist、Monica Paravidino、Anke Hummel、Jessica Rehdorf、Romano V. A. Orru、Ulf Hanefeld、Uwe T. Bornscheuer
DOI:10.1002/ejoc.201000193
日期:2010.5
The kineticresolution of a series of acetates of tertiary alcohols bearing a nitrogen substituent has been studied by using several recombinant carboxyl esterases and variants thereof expressed in E. coli. Most of the enzymes were active in the conversion of these tertiary alcohols and excellent enantioselectivities were achieved in the synthesis of three 2-(pyridin-x-yl)but-3-yn-2-ols with the nitrogen
Hydrolase-Catalysed Preparation of Chiral α,α-Disubstituted Cyanohydrin Acetates
作者:Jarle Holt、Isabel W. C. E. Arends、Adriaan J. Minnaard、Ulf Hanefeld
DOI:10.1002/adsc.200700053
日期:2007.6.4
The enzymatichydrolysis of esters of tertiary alcohols has long been a challenge. In particular their kinetic resolutions have virtually not been addressed. Here we describe the successful kinetic resolution of α,α-disubstituted cyanohydrin acetates, a type of protected tertiary alcohols that form particularly interesting building blocks in organic synthesis. Utilising Subtilisin A the hydrolysis reaction