Synthetic Studies of the Yunnaneic Acids

The total syntheses of yunnaneic acid C, yunnaneic acid D, and rufescenolide are described. The highly substituted bicyclic cores of these molecules were synthesized in a single step via a oxidative dearomatization/Diels-Alder cascade sequence from simple precursors. Dimerization studies towards yunnaneic acid A and yunnaneic acid B are also described, which resulted in the synthesis of several novel, non-natural structures.