Electron impact mass spectrometry of some amino derivatives of 1,4-benzodiazepines

The electron impact mass spectra of some mono- and diamino derivatives of 5-phenyl-1,4-benzodiazepines have been determined, and their fragmentation pattern elucidated with the aid of deuterium-labelled derivatives, high resolution mass measurements and metastable analysis. The most significant ions are derived from the loss of the amino residues, and from the contraction of the seven-membered benzodiazepine system to give smaller rings.