The invention relates to compounds of the general formula (I): ##STR00001## wherein Ar is optionally substituted aryl or heteroaryl; A is (i) --O--, --S--, --SO.sub.2--, --NH--, (ii) a C.sub.1-4-alkyl- or C.sub.1-6-acyl-substituted nitrogen atom or (iii) a C.sub.1-8-alkylene chain or a heteroalkylene chain having 2 to 8 chain atoms, which optionally contains at least one unsaturation, and which may be substituted and/or contain a bridge to form a saturated or partially or fully unsaturated ring having 3-8 ring members; B is --C(R.sub.4)(R.sub.5)--, --OC(R.sub.4)(R.sub.5)--, --N(R.sub.6)C(R.sub.4)(R.sub.5)--, --N(R.sub.6)--, --O--, --S-- or --SO.sub.2--; R is optionally substituted C.sub.3-8-cycloalkyl, aryl or heteroaryl; R.sub.1 is (i) a saturated or unsaturated azacyclic or aminoazacyclic ring, or a saturated diazacyclic or aminodiazacyclic ring, which has 4 to 7 ring members, or a saturated aminoazabicyclic, azabicyclic or diazabicyclic ring which has 7 to 10 ring members, which rings optionally are substituted in one or more positions, or a group --[C(R.sub.4)(R.sub.5)].sub.xN(R.sub.2a)(R.sub.3a)]; R.sub.2a, R.sub.3a, R.sub.4, R.sub.5, R.sub.6 and x are as defined in the claims, and n is 0 or 1; and pharmaceutically acceptable salts, hydrates and prodrug forms thereof. The compounds may be prepared by per se conventional methods and can be used for treating a human or animal subject suffering from a serotonin-related disorder, such as eating disorders, especially obesity, memory disorders, schizophrenia, mood disorders, anxiety disorders, pain, sexual dysfunctions, and urinary disorders The invention also relates to such use as well as to pharmaceutical compositions comprising a compound of formula (I).