Synthesis of certain benzo- and pyridodiazepines likely to possess tranquilizing effect.

The synthesis of certain 1.5-benzodiazepinediones, some of their oxygen-free analogues and a number of the 7-nitro derivatives is described. Condensation of 3.4-diaminopyridine with diethylmalonate instead of affording the expected pyridodiazepine, yielded an imidazopyridine, the structure of which was inferred from spectral data Nevertheless, the pyridodiazepine was obtained by condensing the diamino-heterocycle with malonyl dichloride.