This invention provides an anorectic or anti-obesity composition comprising a compound of the formula (I):formula (I):a pharmaceutically acceptable salt or solvate thereof,whereinR1 is optionally substituted lower alkyl,Y is —S(O)n- wherein n is 1 or 2, or —CO—,R2 is hydrogen or lower alkyl,R7 is hydrogen or lower alkyl,X is lower alkylene, lower alkenylene, arylene, cycloalkylene or the like, andZ is lower alkyl, optionally substituted carbocyclyl, optionally substituted heterocyclyl or the like.