Enantioselective syntheses of the proposed structures of cytotoxic macrolides iriomoteolide-1a and -1b.

Enantioselective total syntheses of the proposed structures of macrolide cytotoxic agents iriomoteolide-1a and -1b have been accomplished. The synthesis was carried out in a convergent and stereoselective manner. However, the present work suggests that the reported structures have been assigned incorrectly. The synthesis features Julia-Kocienski olefination, Sharpless asymmetric epoxidation, Brown asymmetric crotylboration, a Sakurai reaction, an aldol reaction, and enzymatic resolution as the key steps.