Synthesis of antimicrofilament marine macrolides: synthesis and configurational assignment of a C5-C16 degradation fragment of reidispongiolide A.

Reidispongiolide A is a representative member of the sphinxolide/reidispongiolide group of cytotoxic 26-membered macrolides of marine origin. By interacting with actin in the cell cytoskeleton, the reidispongiolides and sphinxolides are potent microfilament destabilizing agents that represent a promising mechanism of action for developing novel anticancer drugs. An aldol-based synthesis of a library of diastereomers of C(8)-C(16) and C(5)-C(16) fragments and detailed NMR comparison with a reported degradation fragment enabled a configurational assignment for a major part of the reidispongiolide macrocyclic core, thus setting a solid foundation for ongoing synthetic efforts.