| abstract |
The present invention provides an I Kur blocker useful for the prevention or treatment of cardiac arrhythmias such as atrial fibrillation. SOLUTION: (In the formula, ring X represents benzene or pyridine. R 1 represents substituted alkyl. R 2 represents an optionally substituted aryl or an optionally substituted heterocyclic group. R 3 represents hydrogen or R 4 represents hydrogen, halogen or alkyl, R 5 represents hydrogen or alkyl, and R 6 and R 7 are the same or different and each represents hydrogen or halogen.) Or a pharmaceutically acceptable salt thereof. [Selection figure] None |