PYRAZOLOPYRIMIDINONE DERIVATIVES, THEIR PREPARATION AND THEIR USE

摘要

Pyrazolopyrimidinone derivatives, which have the following formula, their preparation and their use.Such derivatives show potent activity against PDE5 proved by pharmacological test, and parts of them show distinctly more powerful inhibiting activity against PDE5 than against PDE6. A majority of the compounds has low toxicity. Such derivatives are useful clinically in improving or treating the disorders or diseases of cardiovascular system or urinary system, and especially in improving or treating the disorders or diseases including erection dysfunction.