Thienopyrimidines of the formula (I) and their physiologically acceptable salts, in which R
1
, R
2
and X are as defined in claim 1, exhibit phosphodiesterase V inhibition and can be employed for the treatment of illnesses of the cardiovascular system and for the treatment and/or therapy of impotence.
1
variety of 2-methylpyrimidin-4(3 H)-ones promoted by chlorotrimethylsilane was investigated. A simple and flexible general procedure for the synthesis of a series of fused pyrido[1,2- A]pyrimidin-4-ones is proposed. A set of functionally and structurally diverse pyrido[1,2- A]pyrimidin-4-ones were obtained in high yields.