There is provided compounds of formula IA and of formula IB,
1
wherein R
1
, R
2
, R
3
, Het
1
and X have meanings given in the description, which are useful in the curative and prophylactic treatment of medical conditions for which inhibition of a cyclic guanosine 3′,5′-monophosphate phosphodiesterase (e.g. cGMP PDE5) is desired.
提供了公式IA和公式IB的化合物,其中R1、R2、R3、Het1和X的含义在说明中给出,这些化合物在治疗和预防需要抑制环状
鸟苷酸3',5'-单
磷酸磷酸二酯酶(例如cGMP PDE5)的医疗状况方面是有用的。