Total Synthesis of the Pentacyclic Alkaloid Ascididemin

Abstract

The antileukemic alkaloid ascididemin (1) was prepared from quinoline-5.8-quinone(Q) by oxidative anination with o-aminoacetophenone ( 3 ) .followed by acid catalysed cyclisation and subsequent one pot annelation o f ring E. Ascididenin (A), a pentacyclic alkaloid with antileukemic activity, was isolated 2 by Kobayashi and co-workers from t h e Okinawan tunicate Oideanum sp. in l a w yield