The present invention relates to a compound represented by formula [1] or a pharmaceutically acceptable salt thereof:In formula [1], one of X and Y is CH and the other is oxygen or sulfur； R is hydrogen, etc.； Z is hydrogen, etc.； Ar is phenyl, etc.； and n is 1 or 2 and or m is 1 or 2, excluding compounds where n is 2 and m is 2 simultaneously. Also provided is a pharmaceutical composition comprising a compound of formula [1] or a pharmaceutically acceptable salt thereof as an active ingredient. The composition is usable as an agent for the prevention or treatment of depression, panic disorder, anxiety, obsessive-compulsive disorder, chronic pain, fibromyalgia, obesity, stress urinary incontinence, and overactive bladder.
