Fused-ring amino-pyrazines as bradycardiac agents

摘要

Compounds of the formula <IMAGE> wherein A and B, which may be the same or different, each represent methylene, (alkyl of 1 to 3 carbon atoms)-methylene, ethylene or (alkyl of 1 to 3 carbon atoms)-ethylene; R1 is hydrogen, alkyl of 1 to 6 carbon atoms, cycloalkyl of 3 to 7 carbon atoms, alkenyl of 3 to 6 carbon atoms, phenyl-(alkyl of 1 to 3 carbon atoms), halophenyl-(alkyl of 1 to 3 carbon atoms), alkanoyl of 1 to 3 carbon atoms, phenyl-(alkanoyl of 1 to 3 carbon atoms), halophenyl-(alkanoyl of 1 to 3 carbon atoms), alkoxycarbonyl of 2 to 4 carbon atoms, aralkoxycarbonyl of 8 to 10 carbon atoms or phenyl; one of R2 and R3 is amino and the other is hydrogen, chlorine, bromine, alkyl of 1 to 3 carbon atoms, alkoxy of 1 to 3 carbon atoms, alkoxycarbonyl of 2 to 4 carbon atoms, phenyl or halophenyl; and non-toxic, pharmacologically acceptable acid addition salts thereof. The compounds as well as their salts are useful as bradycardiacs.