A melanin-concentrating hormone antagonist comprising a compound of the
formula: ##STR00001## wherein R is hydrogen atom or a cyclic group which
may be substituted; X is a bond or a spacer having a main chain of 1 to
10 atoms; Y is a spacer having a main chain of 1 to 6 atoms; ring A is
benzene ring which may be further substituted; ring B is a 5- to
9-membered nitrogen-containing non-aromatic heterocyclic ring which may
be further substituted; R.sup.1 and R.sup.2 are the same or different and
are hydrogen atom, a hydrocarbon group which may be substituted or a
heterocyclic group which may be substituted; or R.sup.1 and R.sup.2,
together with the adjacent nitrogen atom, may form a nitrogen-containing
heterocyclic ring which may be substituted; or R.sup.2, together with the
adjacent nitrogen atom and Y, may form a nitrogen-containing heterocyclic
ring which may be substituted; or a salt thereof is useful as a
preventive or therapeutic agent for obesity, etc.