PHARMACEUTICALLY ACTIVE COMPOUNDS.

摘要

Compounds of general formula (1): wherein R1, R2, R3, R4, X, Y and A have the meanings given herein which are useful in the curative and prophylactic treatment of a medical condition for which inhibition of a cyclic guanosine 3 , 5 - monophosphate phosphodiesterase (e.g. cGMP PDE5) is desired.