PROBLEM TO BE SOLVED: To provide compounds, methods and compositions for the modulation of serum uric acid levels (sUA) or the treatment of gout or hyperuricemia.SOLUTION: This invention relates to a pyridine-4-yl-thio-2-alkyl propanoic acid derivative represented by formula (I-K), where X, X, X, Rand Rare CH; Xis N; Yis CR; Yis CR; M is Calkyl; Ris H, CF, CH, OCH, F or Cl; Ris H, Calkyl, Ccycloalkyl, CF, OH, SH, SCH, COOH, CONH, SONHor the like.【課題】血清尿酸値(sUA)の調節、あるいは、痛風または高尿酸血症の処置のための、化合物、方法及び組成物の提供。【解決手段】式(I-K)で表されるピリジン-4-イル-チオ-2-アルキルプロパン酸誘導体。(X1、X3、X4、Ra及びRbはCH;X2はN;Y1はCR1;Y2はCR2;MはC1-3アルキル;R1はH、CF3、CH3、OCH3、F又はCl;R2はH、C1-4アルキル、C3-4シクロアルキル、CF3、OH、SH、SCH3、COOH、CONH2、SO2NH2等)【選択図】なし