During our efforts to develop a novel class of selective V(1A) receptor antagonists, the N-methylbenzanilide structure was applied to a 4,4-difluoro-1-benzazepine derivative, 4, which is a selective V(1A) receptor antagonist. Further structural modifications gave 16a with high V(1A) affinity and V(2)/V(1A) selectivity (K(i)=5.71 nM, V(2)/V(1A)=140) and potent V(1A) receptor antagonist activity (ID(50)=0.0080 mg/kg iv).