The present invention provides novel sulfonamide compounds having TRPM8 antagonistic activity and useful as a medicine. Specifically, the present invention provides a sulfonamide compound of formula (I) or a pharmaceutically acceptable salt thereof: wherein Ring A is a group of formula (i), (ii), or (ix): R4 is optionally substituted alkyl, X1 and X2 are each independently tetrazolyl, tetrazolinonyl, optionally substituted triazolyl, triazolinonyl, oxadiazolonyl, optionally substituted alkanoylaminomethyl, or optionally substituted alkylsulfonylaminomethyl, or R4 and X2 combine each other at their terminals together with the adjacent benzene to form indazolinonyl or benzoisoxazolonyl, and other symbols are the same as defined in the specification.本發明係提供具有TRPM8阻斷效果且作為醫藥有用的新穎磺胺化合物。具體而言，本發明係提供式(I)所示之磺胺化合物或其藥理上容許之鹽。[式中，環A為下式(i)、(ii)、或(ix)：R4為可經取代之烷基，X1及X2係各自獨立為四唑基、四唑啉酮基、可經取代之三唑基、三唑啉酮基、二唑酮基、可經取代之烷醯基胺基甲基、或可經取代之烷基磺醯基胺基甲基，或者，R4及X2係相互以其末端鍵結而與鄰接之苯形成吲唑啉酮基、或苯并異唑酮基，其他符號係如說明書所記載]。
