| abstract |
A compound represented by the formula (I): wherein R1 is an oxo group, =N-R or the like; a group represented by the formula: is a group represented by the formula:;R2 is a group represented by the formula: or a salt thereof. The compound of the present invention is useful as a drug for the prophylaxis or treatment of circulatory diseases, metabolic diseases and/or central nervous system diseases. |