Patent ID: 6693205
Filing Date: 2004-02-17
Classification: C07D

Abstract:
A process for producing an optically active (2R, 3S)-epoxide of the formula (1): or its enantiomer wherein each of R1 and R2 is independently selected from the group consisting of hydrogen, optionally substituted alkyl, aryl, aralkyl, and alkaryl groups, and amine-protecting groups, and R3 is selected from hydrogen and optionally suitably protected alkyl, cycloalkyl, aryl, aralkyl and alkaryl groups, said process comprising subjecting an optically active (2S,3S)-alcohol offormula (2): or its enantiomer, wherein X is a leaving group, to a Mitsunobu reaction to obtain a Mitsunobu reaction product and cyclising the Mitsunobu reaction product to form an optically active (2R,3S) epoxide of the general formula (1), the stereochemistry of the optically-active (2S,3S)-alcohol or its enantiomer being inverted in said Mitsunobu reaction.