Asymmetric Synthesis of Ramariolides A and C through Bimetallic Cascade Cyclization and Z–E Isomerization Reaction

A short and flexible asymmetric synthesis of ramariolides A and C was accomplished. A bimetallic catalytic system consisting of Pd–Cu-mediated cascade cyclization, unprecedented Z–E isomerization by a Ru-based metathesis catalyst, and late-stage stereoselective epoxidation are the key steps involved in the synthesis.