Compounds represented by general formula (I) (wherein A represents a C cycloalkyl group optionally substituted by 1-3 substituents selected from among fluoro groups, hydroxide groups and/or a C alkyl groups； R, R and R each individually represents a hydrogen atom, a fluoro group or a C alkyl group； R represents a hydrogen atom or a prodrug group；and Y represents -CH-CHR-CH-NHR, in which R represents a hydrogen atom, a C alkyl group or a C alkoxy group and R represents a hydrogen atom or a prodrug group) and pharmacologically-acceptable salts thereof exhibit a TAFIa-inhibiting activity, and thus are useful as therapeutic drugs for myocardial infarction, angina, acute coronary syndrome, cerebral infarction, deep vein thrombosis, pulmonary embolism, etc.
