| abstract |
Disclosed is a drug having an atrial selective K + channel blocking action. SOLUTION: General formula (1) Wherein R 1 , R 2 , R 3 and R 4 are each independently hydrogen, lower alkyl, etc., and R 2 and R 3 may form lower alkylene , A 1 is lower alkylene optionally substituted with hydroxyl and oxo groups, Y 1 and Y 2 are each independently —N═ or —CH═, and R 5 is It is. [Selection figure] None |