Thermal cyclization experiments with benzoyl-DL-kynurenylglycine and related compounds

Abstract

Thermal cyclization of benzoyl-DL-kynurenylglycine to give a tricyclic 1,4-benzodiazepine derivative is discussed. Proposed formation of an initial pyrrolinone intermediate in this reaction has been supported by cyclization experiments with the analogous acyl dipeptide benzoyl-DL-2- phenacylglycylglycine,which lacks the aromatic amino group of kynurenine. The behaviour of some other related compounds is also considered.