The present invention provides a compound having an effect of regulating differentiation of muscle cells or adipocytes, useful for the prevention and treatment of diseases such as diabetes, obesity, dyslipidemia and the like and having an excellent medicinal effect. The present invention provides a compound represented by the formula: [wherein each symbol is as described in the specification] or a salt thereof.本発明は、筋細胞または脂肪細胞分化調節作用を有し、糖尿病、肥満症、脂質異常症等の疾患等の予防・治療に有用であり、かつ優れた薬効を有する化合物を提供する。本発明は、式：〔式中、各記号は明細書記載のとおり〕で表される化合物またはその塩を提供する。
