The present invention provides a compound represented by the general formula (I) or pharmacologically acceptable salts thereof,[in formula, A represents C3~C12 cycloalkyl group optionally substituted by 1~3 substituents selected from fluoro group, hydroxyl group, C1~C6 alkyl and the like；R1, R2 and R3 respectively and independently represent hydrogen, fluoro group or C1~C6 alkyl； R4 represents hydrogen or prodrug group； Y represents -CH2-CHR5-CH2-NHR6 (wherein, R5 represents hydrogen, C1~C6 alkyl or C1~C6 alkoxy group； R6 represents hydrogen or prodrug group.)].The compound has the inhibition activity to TAFIa enzyme and is useful as a therapeutic agent for cardiac infarction, stenocardia, acute coronary syndrome, brain infarction, deep vein thrombosis, pulmonary embolism and the like.一種以下列通式(I)表示之化合物或其在藥理上可容許的鹽[式中，A表示也可經選自氟基、羥基、C1~C6烷基等當中1~3個取代的C3~C12環烷基，R1、R2及R3各自獨立而表示氫原子、氟基或C1~C6烷基，R4表示氫原子或前驅藥基，Y表示-CH2-CHR5-CH2-NHR6(在此R5表示氫原子、C1~C6烷基或C1~C6烷氧基，R6表示氫原子或前驅藥基。)等。]，具有TAFIa酵素抑制活性，且有用於作為心肌梗塞、心絞痛、急性冠狀動脈功能不全症候群、腦梗塞、深部靜脈血栓症、肺栓塞症等之治療藥。
