Studies on the syntheses of heterocyclic compounds. Part CDXXXII. Synthesis of (±)-thalicsimidine by a possible biosynthetic route

Abstract

Phenolic oxidative coupling of the diphenolic benzylisoquinolines (21) and (22) with potassium ferricyanide afforded the aporphine (3) and the spirocyclohexadienones (23a and b), respectively. The dienones (23a and b) were treated with acid to give two aporphines (4) and (5). Methylation of compounds (3) and (5) with diazomethane gave (±)-thalicsimidine (1).