Total synthesis of (±)-13-epineostenine

An efficient total synthesis of (±)-13-epineostenine (2) has been achieved in 15 steps and 17% overall yield. This approach involved the key alkylation/Michael additions of the central 1,4-cyclohexanedione monoethylene acetal and all of the stereocenters on central cyclohexane moiety were generated in highly stereoselectivity.