PROBLEM TO BE SOLVED: To provide a novel benzene derivative and a novel thiophene derivative useful as a VAP-I inhibitor, a pharmaceutical agent for the prophylaxis and treatment of VAP-I associated diseases, and the like.SOLUTION: This invention relates to a compound represented by formula (I), where each symbol is defined in the specification, or its pharmaceutically acceptable salt.【課題】ＶＡＰ－１阻害剤、ＶＡＰ－１関連疾患の予防および治療用医薬などとして有用な新規ベンゼン誘導体、チオフェン誘導体を提供すること。【解決手段】式（Ｉ）:［式中、各記号は本明細書中で定義した通りである。］で表される化合物、またはその医薬上許容され得る塩。【選択図】なし
