Patent ID: 6960610

Claim:
A method of treating cardiac or cardiovascular disease, wherein said cardiac or cardiovascular disease is arrhythmia comprising administering to subject in need thereof an effective amount of a compound of formula (I) wherein R 1 is hydrogen or acyl, alkenyl, cycloalkyl or alkyl, all of which are optionally substituted with one or more of the following groups: hydroxy, alkoxy, amino, N-alkylamino, N,N-dialkylamino, halogen, cycloalkyl, optionally substituted phenyl or alkoxycarbonyl; R 2 is hydrogen or alkyl; R 3 and R 4 , which are the same or different, independent of each other, is hydrogen, halogen, hydroxy, mercapto or amino which is optionally substituted with alkyl or aralkyl; and R 5 is alkyl substituted with hydroxy, halogen, amino, N-alkylamino, N,N-dialkylamino or mercapto; or a pharmaceutically acceptable salt or hydrate or prodrug thereof, optical or geometric isomers or tautomeric forms or mixtures thereof.