Biocatalytic asymmetric and enantioconvergent hydrolysis of trisubstituted oxiranes
摘要:
Asymmetric biohydrolysis of trialkyl oxiranes (+/-)-1a-3a using the epoxide hydrolase activity of whole bacterial cells proceeded in an enantioconvergent fashion and thus led to the corresponding (R)-configurated vicinal diols Ib 3b in Lip to 97% enantiomeric excess (e.e.) as the sole product. The mechanism of this enantioconvergence vas investigated by O-18-labelling experiments and it was found that both enantiomers were hydrolysed with opposite regioselectivity. (C) 2001 Elsevier Science Ltd. All rights reserved.
Demonstration of a Common Concerted Mechanistic Pathway for the Acid-Catalyzed Cyclization of 5,6-Unsaturated Oxiranes in Chemical and Enzymatic Systems