Asymmetric Total Syntheses of Two Phlegmarine-Type Alkaloids, Lycoposerramines-V and -W, Newly Isolated fromLycopodium serratum

Abstract

Two new Phlegmarine-type alkaloids, lycoposerramines-V and -W, were isolated from Lycopodium serratum, and their structures including the absolute configuration were established by asymmetric total synthesis involving such key steps as Johnson−Claisen rearrangement, asymmetric allylation, and ring-closing metathesis (RCM)- or SmI₂-mediated stereoselective piperidine ring construction.