Compounds of the formula (I): ##STR00001## (wherein A is an optionally substituted straight-chain hydrocarbon having 1 to 6 carbon atoms, which is optionally intervened by oxygen or nitrogen atom; Ar.sup.1 is aryl or heteroaryl, any of which is optionally substituted; n is 0 or 1; R.sup.0 is hydrogen, or lower alkylene attached to an arbitrary, bondable position of A; T, U, V and W are independently nitrogen atom or optionally substituted methine, and at least two of T, U, V and W are said methine group; X is --N(SO.sub.2R.sup.1)--, --N(COR.sup.2)-- or --CO--; Y is --C(R.sup.3)(R.sup.4)--, --O-- or --N(R.sup.5)--; Z is methine or nitrogen atom) exhibit NPY antagonistic activities and are useful as agents for the treatment of various diseases related to NPY, for example, cardiovascular disorders such as hypertension, nephropathy, heart disease, vasospasm, arteriosclerosis, etc., central nervous system disorders such as bulimia, depression, anxiety, seizure, epilepsy, dementia, pain, alcoholism, drug withdrawal, circadian rhythm disorders, schizophrenia, etc., metabolic diseases such as obesity, diabetes, hormone abnormality, hypercholesterolemia, hyperlipidemia, etc., sexual and reproductive dysfunctions, and gastro-intestinal motility disorder.