PROVIDED ARE A COMPOUND HAVING AN EXCELLENT HYPOGLYCEMIC ACTION, OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF, AND A PHARMACEUTICAL COMPOSITION HAVING AN EXCELLENT THERAPEUTIC EFFECT AND/OR PROPHYLACTIC EFFECT ON TYPE 1 DIABETES, TYPE 2 DIABETES, AND THE LIKE, WHICH CAUSE AN INCREASE IN THE BLOOD SUGAR LEVEL DUE TO ABNORMAL SUGAR METABOLISM. A COMPOUND REPRESENTED BY GENERAL FORMULA (I), OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF, IS DISCLOSED.