Utilization of Protopine and Related Alkaloids. XV. Photolysis of 4-Methyl-1-oxoanhydroberberine

Abstract

Photolysis of 4-methyl-1-oxoanhydroberberine (9) in the presence of nitrosobenzene gives two isomeric photoadducts (11) and (12). In the presence of diethyl azodicarboxylate, 9 affords two different types of photoadduct (13) and (14). These photoadducts are considered to be formed by the photochemically allowed [2_s+2_s+2+_s] cycloaddition reactions.