Abstract
Lewis acid (MgCl2, ZnCl2) mediated cyclodehydration of a linear tripeptide comprised of three amino acid units in the order of anthranilic-anthranilic-glycine (C-terminal anthranoyl-anthranilate methyl ester) furnished the tricyclic quinazolino[3,2-d][1,4] benzodiazepine ring system found in various biologically active natural alkaloids. This methodology, implemented with a tripeptide encompassing the sequence of anthranilic-anthranilic-tryptophan methyl ester, furnish the first total synthesis of asperlicin D.