1,2,3,4-Tetrahydro-1-[(4-methylphenyl)sulfonyl]-5H-1-benzazepin-5-one is an intermediate used to prepare nonpeptide vasopressin V2 receptor antagonist tetrahydro-1H-benzazepines. It is also used to synthesize 4'-[(4,4-difluoro-5-methylidene-2,3,4,5-tetrahydro-1H-1-benzoazepin-1-yl)carbonyl]-2-phenylbenzanilide derivatives as non-peptide arginine vasopressin antagonists for both V1A and V2 receptors.