Structure and biosynthesis of chlidanthine

Abstract

The structure of the phenolic Amaryllidaceae alkaloid, chlidanthine, has been determined by NO-dimethylation to give (–)-galanthamine methiodide, which was in turn prepared from (–)-galanthamine via(–)-epigalanthamine. The relative stereochemistry of the pair of epimeric, allylic alcohols derived from Pummerer's ketone has been determined. The conversion of these alcohols into allylic chlorides with thionyl chloride and with trisdimethylaminophosphine and carbon tetrachloride is described. Biosynthetic conversion of tritiated galanthamine and narwedine into chlidanthine has been observed in Chlidanthus fragrans Herb.