| abstract |
A 4-quinolinone derivative represented by general formula (1) or a salt thereof, and an intermediate for use in the production thereof; and a medicinal composition containing the compound as the active ingredient: wherein R?1 and R2¿ represent each H, halogen, cyano, optionally halogenated lower alkyl, lower alkylsulfonyl, lower alkylsulfinyl, lower alkylthio or lower alkoxy, or optionally substituted phenylsulfonyl, phenylsulfinyl or phenylthio; and R?3 and R4¿ represent each H, optionally halogenated lower alkyl or cycloalkyl, or optionally substituted pyridyl, furanyl or phenyl, or R?3 and R4¿ may be combined together to represent a four- to six-membered ring. The compound (1) and salt thereof have an excellent effect of potassium channel activation and are useful as a preventive and remedy for, for example, circulatory and bronchial diseases. |