Connecting Tyrosine and Tryptophan Units of Diazonamide A and Azonazine by a Diastereodivergent Arylative Dearomatization

Abstract

We report the Friedel-Crafts coupling of a tyrosine unit with tryptophan-derived pyrrolindolenium ions which are configurationally stable. The reaction allowed the stereoselective and divergent access to the required quaternary stereocenters found in diazonamide A and azonazine at the junction of the tyrosine and tryptophan units.