Total Synthesis of Cytotoxic Macrolide Amphidinolide B1 and the Proposed Structure of Amphidinolide B2

The first enantioselective total syntheses of cytotoxic macrolide amphidinolide B1 and the proposed structure for amphidinolide B2 have been accomplished. Key features of the syntheses include a diastereoselective aldol condensation, a spontaneous Wadsworth-Emmons macrocyclization and a directed epoxidation/elimination sequence.