Substitution of the amino group of 2-amino-3H-1, 4-benzodiazepines such as 1 and 2 with primary amines and hydroxylamines was investigated and the 2-substituted compounds 3-19, 21 and 37 were synthesized as shown in Table I. In the case of the reaction with hydroxylamine, however, a 2-aminomethylquinazoline 3-oxide (20) was obtained from a 2-amino-and a 2-methylamino-benzodiazepines (1 and 3) in addition to 2-hydroxyamino-1, 4-benzodiazepine (21). This data show that ring opening at the N-4 : C-5 double bond occurred. A similar ring opening in a 2-methylamino-1, 4-benzodiazepine 4-oxide (4) furnished a quinazoline-2-carboxaldehyde oxime 3-oxide (40). The derivatives of 21 and its oxide (37) were prepared as exemplified by the synthesis of oxadiazolo [4, 3-a] [1, 4]-benzodiazepines (25 and 39).