Abstract: A large conductance calcium-activated K channel opener comprising as an active ingredient a nitrogen-containing 5-membered heterocyclic compound represented by the following formula (I): wherein X represents N—R4, O or S, R1 and R2 each independently represent hydrogen, halogen, carboxyl, amino, lower alkyl, lower alkoxycarbonyl, lower alkenyl, cyclo-lower alkyl, carbamoyl, aryl, heterocyclic or heterocyclic-substituted carbonyl group, R3 represents aryl, heterocyclic or lower alkyl group, and R4 represents hydrogen or lower alkyl group, or a pharmaceutically acceptable salt thereof.

Abstract: A large conductance calcium-activated K channel opener comprising as an active ingredient a nitrogen-containing 5-membered heterocyclic compound represented by the following formula (I): wherein X represents N—R4, O or S, R1 and R2 each independently represent hydrogen, halogen, carboxyl, amino, lower alkyl, lower alkoxycarbonyl, lower alkenyl, cyclo-lower alkyl, carbamoyl, aryl, heterocyclic or heterocyclic-substituted carbonyl group, R3 represents aryl, heterocyclic or lower alkyl group, and R4 represents hydrogen or lower alkyl group, or a pharmaceutically acceptable salt thereof.

Abstract: A pyrazolopyrimidine derivative of the formula [I] wherein R1 is an optionally substituted aromatic ring group, an optionally substituted lower alkyl group or an optionally substituted amino group; R2 is an optionally substituted aromatic ring group; R3 is an optionally substituted lower alkyl group; and R4 is a hydrogen atom, a lower alkyl group, a halogen atom, a nitro group or an amino group; or a pharmaceutically acceptable salt thereof is useful as an antagonist of CRF receptor.

Abstract: There is disclosed a large conductance calcium-activated K channel opener comprising a compound of the formula (I): wherein R1 is aminosulfonyl, alkylsulfonyl, etc., R2 is hydrogen or halogen, R3 and R4 are hydrogen, halogen, alkyl or alkoxy, Ring A is benzene, pyridine, etc., and Ring Q is pyrazol, isoxazol, etc., and Ring Q and Ring A may be combined to each other to form a fused ring of the formula: where X is S or O, R5 is halogen, alkyl, etc., and R3 and R4 are the same as mentioned above, or a pharmaceutically acceptable salt thereof as an active ingredient.