Synthesis of 5 H ‐tetrazolo[5,1‐ c ][1,4]benzodiazepines

A three step synthesis of 5 H ‐tetrazolo[5,1‐ c ][1,4]benzodiazepin‐11‐ones 8a‐d via the reaction of a substituted benzyl azide and ethyl cyanoformate is described. The derived lactams are converted to the corresponding 11‐thiones 9a‐d and, through the S ‐methylated derivatives, to the 11‐amino analogs 11a‐f. All of the described compounds are representatives of a novel ring system.