The present invention is a compound having the general formula (I), (II), or (III) or a pharmacologically acceptable salt, solvate, or hydrate thereof, and a pharmaceutical composition containing such a compound, or its pharmacologically acceptable ester, or other pharmacologically acceptable derivative thereof as an active ingredient. The compound has an excellent ACAT 2-inihibiting activity by a mechanism different from that of a statin drug and is useful as a therapeutic or prophylactic agent for obesity, adiposis, hyperlipidemia, hypercholesterolemia, disorder of lipid metabolism, and arteriosclerosis, as well as obesity-derived hyperlipidemia, hypercholesterolemia, disorder of lipid metabolism, arteriosclerosis, and hypertension.
