A compound of the formula: ##STR1## wherein Ar.sup.1 and Ar.sup.2 independently represent an optionally substituted aromatic group; P and Q independently represent a divalent aliphatic hydrocarbon group having at least 2 carbon atoms and optionally having either oxygen or sulfur in the carbon chain; R.sup.1 and R.sup.3 independently represent --CO--R, --CONH--R (R represents a hydrocarbon group or a heterocyclic group) or a hydrocarbon group; R.sup.2 and R.sup.4 independently represent hydrogen or an alkyl group; R.sup.2 and R.sup.4 independently represent hydrogen or an alkyl group; R.sup.1 and R.sup.2 or R.sup.3 and R.sup.4, taken together with the adjacent nitrogen atom, may form a nitrogen-containing heterocyclic group; and j represents 0 or 1, or a salt thereof, has excellent GnRH-receptor antagonizing activity and is useful as a prophylactic and therapeutic agent for hormone-dependent and other diseases.
A compound represented by the formula
wherein Ar1 and Ar2 are each an aromatic group optionally having substituents, P and Q are each a divalent aliphatic hydrocarbon group which optionally contains ether oxygen or ether sulfur in a carbon chain and which optionally has substituents, R1 and R3 are each (i) a hydrogen atom, (ii) an acyl group or (iii) an hydrocarbon group optionally having substituents, R2 and R4 are each (i) a hydrogen atom, (ii) an alkyl group optionally having substituents or (iii) an alkylcarbonyl optionally having substituents, R1 and R2 or R3 and R4 each optionally forms, together with the adjacent nitrogen atom, a monocyclic or fused nitrogen-containing heterocyclic group optionally having substituents, j is 0 or 1, a salt thereof or a prodrug thereof are useful as melanin-concentrating hormone antagonists.