Synthesis of macrocyclic terpenoids by intramolecular cyclization XIII

Stereoselective synthesis of cubitene ( 1 ), a novel diterpene isolated from defense secretion of termites, has been accomplished using an intramolecular reaction of α-sulfenyl carbanion with epoxide. Hydride reduction of the ketone 11 obtained by Claisen rearrangement occurred in unexpectedly high stereoselectivity yielding the chlorohydrin 12 with the desired stereochemistry.