A pyridopyrimidine or a naphthyridine derivative of the formula (I):
wherein R
1
is an optionally substituted nitrogen-containing heterocyclic group, etc.; R
2
is H or a lower alkyl group; R
3
is H or an optionally substituted lower alkyl group, etc.; R
4
is H, a lower alkyl group, COOH, etc.; R
5
is a lower alkyl group which may optionally be substituted by an optionally substituted aryl etc.; one of X and Y is CH and the other is nitrogen, or both of X and Y are nitrogen; or a pharmaceutically acceptable salt thereof, these compounds exhibiting excellent PDE V inhibitory activities, and being useful in the prophylaxis or treatment of penile erectile dysfunction, etc.
公式(I)中的
吡啶并
嘧啶或
萘啶衍
生物,其中R1是可选取代的含氮杂环基团等;R2是氢或较低的烷基基团;R3是氢或可选取代的较低烷基基团等;R4是氢、较低的烷基基团、COOH等;R5是较低的烷基基团,其可以可选取代芳基等;X和Y中的一个是CH,另一个是氮,或者X和Y都是氮;或其药学上可接受的盐,这些化合物表现出优异的PDE V抑制活性,并且在预防或治疗阴茎勃起功能障碍等方面非常有用。