| abstract |
A xanthine phosphodiesterase V inhibitor having the formula (I), (see formula I) where R4 is a C3-15 cycloalkyl group, with or without one or more substituents, C3-15 cycloalkenyl group, with or without one or more substituents, or a heterocycloalkyl group of 3 to 15 members, with or without one or more substituents; useful for treating male (erectile ) and female sexual dysfunction and other physiological disorders. For example, a representative compound of the invention is formula (II). (see formula II) |