The present invention relates to spirocyclic heterocycles of general formula (I) the tautomers, the stereoisomers, the mixtures thereof and the salts thereof, particularly the physiologically acceptable salts thereof with inorganic or organic acids, which have valuable pharmacological properties, particularly an inhibitory effect on signal transduction mediated by tyrosine kinases, the use thereof for the treatment of diseases, particularly tumoral diseases as well as benign prostatic hyperplasia (BPH), diseases of the lungs and airways, and the preparation thereof.