Chiral and stereoselective total synthesis of (-)-mesembranol starting from D-glucose

Abstract

A chiral synthesis of the Sceletium alkaloid (-)-mesembranol 1 is described. The cyclohexane ring in 1 is prepared in an optically active form from D-glucose using Ferrier’s carbocyclisation, and the critical stereochemistry of the quaternary carbon in 1 is constructed stereoselectively via chirality transfer by way of Claisen rearrangement of the cyclohexenol derivative 14a. The perhydroindole skeleton in 1 is effectively generated by intramolecular aminomercuriation of the amino-olefin 18.