Total Synthesis and Absolute Configuration of Curvularides A-E

The first total synthesis of curvularides A-E, isolated from a culture broth of the endophytic fungus Curvularia geniculata, is described. The divergent total synthesis reported herein confirmed the absolute configurations of curvularides A-E and supported that these natural products might be obtained from a common biosynthetic pathway. The key steps involved in the synthesis were the diastereoselective hydrogenation of exo-methylene-γ-butyrolactone to α-methyl-γ-butyrolactone, Sharpless kinetic resolution, Sharpless asymmetric epoxidations, and intramolecular and intermolecular epoxide openings.