PROBLEM TO BE SOLVED: To provide: a compound that has URAT1 inhibitory action； and a URAT1 inhibitor, a blood uric acid level-reducing agent and a pharmaceutical composition that comprise the compound.SOLUTION: The present invention relates to a compound represented by formula (I). [Ris alkyl, cycloalkyl, -Q-A, or the like； Wis N or =C(R)-； Wis N or =C(R)-； Wto Ware each independently N, a substituted/unsubstituted methine group, or the like； X is a single bond, O, or the like； Y is a single bond or (CRR)； and Z is a hydroxy group, COOR, or the like.]SELECTED DRAWING: None【課題】ＵＲＡＴ１阻害作用を有する化合物、並びに該化合物を含むＵＲＡＴ１阻害剤、血中尿酸値低下剤及び医薬組成物の提供。【解決手段】式（Ｉ）で示される化合物。［Ｒ1はアルキル、シクロアルキル、－Ｑ1－Ａ1等；Ｗ1は、Ｎ又は＝Ｃ（Ｒa）－；Ｗ2はＮ又は＝Ｃ（Ｒb）－；Ｗ3～Ｗ5は夫々独立にＮ又は置換／非置換のメチン基等；Ｘは単結合、Ｏ等；Ｙは単結合又は（ＣＲYiＲYi’）n；Ｚは水酸基、ＣＯＯＲ2等］【選択図】なし
