Compounds represented by general formula (I) wherein A represents a C3-12 cycloalkyl group optionally substituted by 1-3 substituents selected from among fluoro groups, hydroxide groups and/or a C1-6 alkyl groups； R1, R2 and R3 each individually represents a hydrogen atom, a fluoro group or a C1-6 alkyl group； R4 represents a hydrogen atom or a prodrug group；and Y represents -CH2-CHR5-CH2-NHR6, in which R5 represents a hydrogen atom, a C1-6 alkyl group or a C1-6 alkoxy group and R6 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.
