Synthesis of C13C22 fragment of the marine sponge polyketide callystatin A

We wish to report here our initial efforts towards the total synthesis of callystatin A, describing the synthesis of the C13C22 fragment. This asymmetric approach uses an efficient syn-aldol reaction, and a diastereoselective epoxidation of an allylic alcohol with m-CPBA followed by epoxide opening with Me2CuLi.