Synthesis of Novel 13a-(omega-Aminoalkyl)-8-oxoberbines by Means of Reaction of Homophthalic Anhydride with 1-Substituted 3,4-Dihydroisoquinolines. An Unexpected Formation of a Pyrrolo[3,4-i] berbindione

摘要

The reaction of 1-[-(N-acylated amino)alkyl]-3,4-dihydroisoquinolines (7a, 7b, 7c, 7d, 7e) with homophthalic anhydride (1) leads to the formation of 8-oxo-13a-[(N-acylated amino)alkyl]-8H-dibenzo[a,g]quinolizine-13-carboxylic acids (8a-e) with predomination of cis diastereomers, together with small amount of trans-8a. cis-13a-[(N-Cbzaminomethyl)]-8-oxo-dibenzoquinolizine-13-carboxylic acid (cis-8a) cyclized to the unknown dibenzo[a,g]pyrrolo[3,4-i]quinolizinedione (10) upon moderate heating in methanol.