Total Synthesis of Pestalotioprolide G and Putative Structure of Pestalotioprolide H.

A concise and convergent route for the stereoselective total synthesis of cytotoxic macrolides pestalotioprolides G and H has been developed for the first time. Intramolecular Heck coupling has been chosen to cyclize the 14-membered macrocycle. This synthetic study strongly suggests that the proposed structure of pestalotioprolide H may need to be corrected as the spectroscopic data on the synthesized molecule deviate from the values reported for the isolated natural product.