PYRIMIDO[5,4-D]PYRIMIDINES, MEDICAMENTS COMPRISING THESE COMPOUNDS, THEIR USE AND PROCESSES FOR THEIR PREPARATION

摘要

The present invention relates to pyrimido¢5,4-d!pyrimidines of the general formula (See Fig. I) in which Ra to Rc are as defined in Claim 1, their tautomers, their stereoisomers and their salts, in particular their physiologically tolerated salts with inorganic or organic acids or bases which have valuable pharmacological properties, in particular an inhibiting action on signal transduction mediated by tyrosine kinases, their use for the treatment of diseases, in particular tumour diseases, and their preparation.