The lipase mediated kinetic resolution of pharmaceutically important beta-hydroxy nitrites is described in high enantionteric excesses and good yields. Some of the chiral beta-hydroxy nitriles have been employed in the synthesis of P-adrenergic blocking agents such as propranolol, alprenolol and moprolol. This protocol has also been extended for the enantiopure preparation of 5-(4-tosyloxymethyl)-1,3-oxazolidine-2-one and 3-liydroxy-4-tosyloxybutaiieiiitrile, chiral intermediates of high synthetic value. (c) 2005 Elsevier Ltd. All rights reserved.
Lipase-mediated resolution of 3-hydroxy-4-trityloxybutanenitrile: synthesis of 2-amino alcohols, oxazolidinones and GABOB
Lipase-mediated kinetic resolution of 3-hydroxy-4-trityloxybutanenitrile gave the (S)-alcohol and (R)-acetate in good yields and high enantioselectivities. The resolution using Pseudomonas cepacia lipase (Burkholderia cepacia) immobilized on modified ceramic particles (PS-C) in diisopropyl ether gave the best results. The use of base additives in this transesterification drastically reduces the reaction time without effecting the yields or enantioselectivities. Resolved 3-hydroxy-4-trityloxybutanenitrile has been utilized for the synthesis of enantiomerically pure 5-tosyloxymethyl-1,3-oxazolidine-2-one, which is an important intermediate for the preparation of beta-adrenergic blocking agents and oxazolidinone based antimicrobial agents. Enantiomerically pure (R)-3-hydroxy-4-trityloxybutanenitrile and (S)-5-tosyloxymethyl-1,3-oxazolidine-2-one have been utilized in the enantioconvergent synthesis of (R)-GABOB. (c) 2006 Published by Elsevier Ltd.
Production of (S)-4-chloro-3-hydroxybutyronitrile using microbial resolution
作者:Toshio Suzuki、Hideaki Idogaki、Naoya Kasai
DOI:10.1016/0960-894x(96)00475-1
日期:1996.11
A new production procedure of (S)-4-chloro-3-hydroxybutyronitrile was developed using microbial resolution. The resting cells of Pseudomonas sp. OS-K-29 preferentially converted (R)-4-chloro-3-hydroxybutyronitrile to the corresponding 1,2-diol by the dehalogenating activity so that (S)-4-chloro-3-hydroxybutyronitrile (94.5 %ee) was obtained from the racemate in 40% yield at the microbial resolution step. Copyright (C) 1996 Elsevier Science Ltd
KO SOO Y.; MASAMUNE HIROKO; SHARPLESS K. B., J. ORG. CHEM., 52,(1987) N 4, 667-671
作者:KO SOO Y.、 MASAMUNE HIROKO、 SHARPLESS K. B.
DOI:——
日期:——
Total synthesis of (R)-glycerol acetonide and the antiepileptic and hypotensive drug (-)-.gamma.-amino-.beta.-hydroxybutyric acid (GABOB): use of vitamin C as a chiral starting material
作者:Michael E. Jung、Teresa J. Shaw
DOI:10.1021/ja00540a022
日期:1980.9
Ascorbic acid (Vitamin C) (9) is shown to be a useful, inexpensive chiral starting material for natural products synthesis. It is converted in high yield via two synthetic operations into (R)-glycerol acetonide (7), the more inaccessible enantiomer of glycerol acetonide. Since D-(R)-glyceraldehydeacetonide (4) and the corresponding alcohol 1 have been used in many total syntheses of a wide variety