Abstract
Metathesis on stage: A combined cross-metathesis (CM)/ring-closing metathesis (RCM) approach has led to the stereocontrolled synthesis of iriomoteolide 3a, a smaller but equally cytotoxic congener of amphidinolides. Chemical editing of the molecule has provided non-natural analogues which have comparable anticancer activity to that of the natural product, thereby allowing the iriomoteolides to be used as probe molecules in chemical biology.