The Conversion of Dihydrolycorine to (-)-α-Lycorane

Abstract

Treatment of dihydrolycorine (I) with phosphoryl chloride under mild conditions yielded a chlorohydrin (V). Reduction of this hydrin with zinc in acetic acid followed by reduction with hydrogen and platinum oxide afforded (-)-α-lycorane (VII), the steric structure of which was considered, in view of the sequence of reactions used in this transformation, to be that of the ring-system of dihydrolycorine.