LIPASE-CATALYZED STEREOSELECTIVE THIOTRANSESTERIFICATION OF MERCAPTO ESTERS

Hydrolytic enzymes such as lipases, esterases, and pro-teases have been used extensively as catalysts in enantioselective and regioselective synthesis.1Many chiral synthons like alcohols,2 amines,3 and acids4 have been prepared in high optical purity via enzymatic hydrolysis in water, or via esterification, transesterification, and aminolysis in organic solvents. Surprisingly, very little attention has been paid to the enzymatic resolution of thiols, in spite of their importance as chiral building blocks. In this work we report that lipases can be used for the preparation of optically active thiols. Acetyl thioesters 1 and 2 were chosen as model compounds, because they are versatile intermediates in the synthesis of antihypertensive agents5 and other drugs of clinical interest.6. © 1990, American Chemical Society. All rights reserved.