Synthetic studies on pentacyclic aromatic alkaloids, kuanoniamine A, 11-hydroxyascididemin, and neocalliactine acetate

Article abstract of DOI:10.1016/S0040-4020(97)10153-3

A pentacyclic aromatic alkaloid, kuanoniamine A (6) was synthesized in three steps from 6-methoxybenzothiazole-4,7-dione (8) and 2-aminoacetophenone (9). 11-Hydroxyascididemin (4) was prepared from 5,8-quinolinedione (13, 14) or 1,4-acridinedione (20). The structure of neocalliactine acetate, a derivative of calliactine, was determined to be 5 by total synthesis from 6-methoxy-5,8-quinolinedione (28) and 2-amino-5-methoxyacetophenone (29).