BigPatents India

The invention relates to new compounds of formula (I) which are selective inhibitors of phosphodiesterase, their pharmaceutically receptable salts or their configuration isomers. This invention also provides a method for preparing the compounds of formula (I), and new intermediates which are involved in the routes of synthesizing the compounds of formula (I). The compounds of formula (I) according to the present invention are effective in treating impotence diseases, especially in treating male erectile dysfunction. They also have such characteristics as longer duration of effect and lower toxicity.