Enantioselective Total Synthesis of (–)-Myrifabral A and B

A catalytic enantioselective approach to the myrioneuron alkaloids (–)-myrifabral A and (–)-myrifabral B is described. The synthesis was enabled by a palladium-catalyzed enantioselective allylic alkylation, that generates the C(10) all-carbon quaternary center. A key N-acyl iminium ion cyclization forged the cyclohexane fused tricyclic core, while vinyl boronate cross metathesis and oxidation afforded the lactol ring of (–)-myrifabral A. Adaptation of previously reported conditions allowed for the conversion of (–)-myrifabral A to (–)-myrifabral B.