This product provides a compound represented by a formula (1) or a salt acceptable for the same agent. It has excellent activity of inhibiting flavin oxidase. It can be used as a therapeutic agent or a preventive agent to treat diseases related to xantina oxidase, such as gout and hyperuricemia, Tumor disorders, urinary calculi, hypertension, degreasing, diabetes, cardiovascular diseases, such as arterial infarction or heart failure, kidney disease, such as diabetic nephropathy, chronic obstructive pulmonary disease and other respiratory diseases,Intestinal inflammation or autoimmune diseases and drugs or pharmaceutical ingredients containing compounds or salts as active ingredients. Claim 1: a compound represented by a formula (1) or a salt acceptable to the same agent [wherein R 83044 represents another formula (2) or (3)；R¹ represents an aryl group optionally substituted with one or a plurality of C₁₋₆ alkyl groups,C₁₋₆ alkoxy groups or halogen atoms, OR, NRR which can form a ring or SR, where R and R each independently represents a hydrogen atom, a C₁₋₈ alkyl group optionally substituted with one or a plurality of groups C₁₋₈ alkoxy,a. Halogen atom or hydroxyl group, an optional arilo group, replaced by one or more c833213131 matrix groups；C₁₋₆ alkoxy groups,halogen atoms or cyano groups or a heteroaryl group optionally substituted with one or a plurality of C₁₋₆ alkyl groups,C₁₋₆ alkoxy groups or halogen atoms； R² represents a hydrogen atom, an amino group, or a C₁₋₈ alkyl group optionally substituted with one or a plurality of halogen atoms； X¹ represents CR³ or a nitrogen atom, where R³ represents a hydrogen atom or a halogen atom； and ring A represents a 5- or 6-membered monocyclic heteroarene optionally substituted with 1 to 4 groups selected from the group consisting of a C₁₋₆ alkyl group optionally substituted with one or a plurality of C₁₋₃ alkoxy groups or an atom of halogen,a. One alcox c83216c831832626 is selectively replaced by one or more halogen at
