| abstract |
There are disclosed a large conductance calcium-activated K channel opener comprising a compound of the formula (I): wherein ring A is a 5-membered heterocyclic ring containing any one of O, N or S, which ring may be substituted by R>4<, R>1< is aryl, heterocyclic or heterocycle-substituted carbonyl; R>2< is hydrogen, halogen, carboxy, amino, alkyl, alkoxycarbonyl, alkenyl or cycloalkyl; R>3< is aryl, heterocyclic or alkyl; and R>4< is hydrogen or alkyl, each of substituents may be substituted, or a pharmaceutically acceptable salt thereof as an active ingredient. |