The biocatalyzed stereoselective preparation of polycyclic cyanohydrins

Abstract

The enzyme-mediated preparation of enantiomerically or diastereomerically enriched polycyclic cyanohydrins has been investigated. Oxynitrilase-catalyzed cyanurations gave excellent results with the bicyclic aldehydes tested. On the other hand, enantio- or diastereoselective acylation, catalyzed by lipase PS or subtilisin, proved to be a more versatile methodology, giving good results even with sterically hindered polycyclic cyanohydrins. Specifically, the steroidal cyanohydrin derivative 4b was isolated with a 89% de.