Heterocondensed quinazolones: synthesis and protein-tyrosine kinase inhibitory activity of 3,4-dihydro-1H,6H-[1,4] oxazino-[3,4-b]quinazolin-6-one derivatives.

1-Benzylidene (2-14) and 1-phenylhydrazono derivatives (15-29) of 3,4-dihydro-1H,6H-[1,4]oxazino[3,4-b]quinazolin-6-one (1) were obtained from the condensation reactions of 1 with a series of aromatic aldehydes and by direct diazonium coupling with aryl-diazonium chlorides. The substances were tested for their ability to inhibit the tyrosine kinase activity of SW-620 (human colon carcinoma) cells. Compounds 8, 10, 12 and 13 showed remarkable inhibitory activity.