The preparation of a series of 3-amino-2-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine-1-acetic acid derivatives 5a-y by reductive amination of 2,3,4,5-tetrahydro-1H-1-benzazepine-2,3-dione (7) with L-amino acid derivatives is described. The compounds were tested for inhibition of angiotensin converting enzyme. The structure-activity profile of the series is discussed. Compound 5a was especially potent when tested in dogs for inhibition of angiotensin I pressor response, having an ID50 = 0.07 mg/kg po.