Common synthetic strategy for optically active cyclic terpenoids having a 1,1,5-trimethyl-trans-decalin nucleus: syntheses of (+)-acuminolide, (−)-spongianolide A, and (+)-scalarenedial
method for providing enantiomerically pure bi-, tri-, and tetracyclicframeworks having a 1,1,5-trimethyl-trans-decalin nucleus, and demonstrated their utility for terpenoid synthesis. Thus, we achieved the stereocontrolled total syntheses of (+)-acuminolide as a bicyclic, (−)-spongianolide A as a tricyclic, and (+)-scalarenedial as a tetracyclic terpenoid from the corresponding optically pure cyclic