| abstract |
The present invention provides a compound represented by the formula (I): wherein R 1 is a C?1-6#191 alkyl group optionally substituted by a C?3-10#191 cycloalkyl group, R 2 is a C?2-6#191 alkyl group, R 3 is a hydrogen atom, a C?1-6#191 alkyl group or a halogen atom, and X is —OR 6 or —NR 4 R 5 wherein R 4 and R 6 are each independently a hydrogen atom, an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group, R 5 is an optionally substituted hydrocarbon group, an optionally substituted heterocyclic group or an optionally substituted hydroxy group, or R 4 and R 5 optionally form, together with the adjacent nitrogen atom, an optionally substituted nitrogen-containing heterocycle, or a salt thereof. The compound of the present invention has a superior peptidase inhibitory action and is useful as an agent for the prophylaxis or treatment of diabetes and the like. |