Abstract
Tandem Staudinger and intramolecular aza-Wittig reactions followed by cyclodehydration of the linear N-[N-( 2-azidobenzoyl)-2-aminobenzoyl] glycine ethyl ester furnished the tetracyclic quinazolino[3,2-d][1,4]benzodiazepine-6,9-dione ring system found in some biologically active natural alkaloids. This method was successfully implemented to synthesize asperlicin D from a linear peptide containing ester and azido terminal groups.