Collective total synthesis of PPAPs: Total synthesis of clusianone via intramolecular cyclopropanation

The total synthesis of clusianone was accomplished through the stereoselective construction of a bicyclo[3.3.1]nonane derivative via a three-step sequence, which has been utilized for the total syntheses of nemorosone, garsubellin A, and hyperforin: intramolecular cyclopropanation, formation of a geminal dimethyl group, and regioselective ring opening of cyclopropane. Further elaboration, including chemo- And stereoselective hydrogenation to generate the C7 stereogenic center and cross-metathesis to construct prenyl groups in the side-chains, was employed to complete the total synthesis of clusianone.