The present invention relates to compounds of the general formula (I) in which A, B, R1, R2 and Het have the meaning given in claim 1; Y is a bivalent group of the formula in which D is C1-C3-alkylene, where D may have a substituent R5; R3 is hydrogen, C1-C8-alkyl or together with R4 is C1-C3-alkylene which may have a radical R5a, or together with R5 is C1-C3-alkylene, and R4 is hydrogen, C1-C8-alkyl or together with R3 is C1-C3-alkylene which may have a radical R5a, or together with R5 is C1-C3-alkylene, where R5 together with R5a, where present, are a bond or C1-C3-alkylene; and where one of the following conditions is satisfied: R3 together with R4 is C1-C3-alkylene which may have a radical R5a; or R3 together with R5 is C1-C3-alkylene; or R4 together with R5 is C1-C3-alkylene where the radical A is different from phenyl when the radical B is phenyl or naphthyl; and medicaments which comprise such compounds and the use thereof for the prophylaxis and/or treatment of vasopressin-dependent and/or oxytocin-dependent diseases.