The purpose of the present invention is to provide: a compound having an excellent hypoglycemic activity and an excellent activity of protecting β cells or the pancreas, or a pharmaceutically acceptable salt thereof; and a pharmaceutical composition having an excellent therapeutic and/or prophylactic effect on type-1 diabetes, type-2 diabetes and the like in which glucose metabolism disorders occur to induce the increase in blood glucose levels.A compound represented by general formula (I) or a pharmaceutically acceptable salt thereof.