1-Phenethylisoquinoline alkaloids. Part I. Structure and synthesis of (–)-melanthioidine, a bisphenethylisoquinoline alkaloid

Abstract

The structure of (–)-melanthioidine from Androcymbium melanthioides was elucidated by spectroscopic and degradative studies and its absolute stereochemistry was determined. It is the first example found of a bis-1-phenethylisoquinoline alkaloid.

The (±)- and (–)-melanthioidines were synthesised in good yield by forming the twenty-membered ring in a double Ullmann reaction.