A cannabinoid receptor modulator containing a compound represented by Formula (I.sub.0) ##STR00001## wherein, X is an oxygen atom, etc., R.sup.0 is an optionally substituted acylamino group, ring A.sup.0 is a benzene ring which may further have a substituent in addition to R.sup.0, and ring B is an optionally substituted 5-membered heterocycle, or a salt thereof or a prodrug thereof.