Reaction of 3-diethylamino-1-aryl-, 3-diethylamino-1-aryl-2-phenyl(4-halophenyl)propane-1-ones hydrochlorides with 6-amino-1,3-dimethyluracil results in heterocyclization products, namely 1,3-dimethyl-7-aryl-5,6-dihydro-1H-pyrido[2,3-d]pyrimidine-2,4-diones, 1,3-dimethyl-7-aryl-6-phenyl(4-halophenyl)-5,6-dihydro-1H-pyrido[2,3-d]pyrimidine-2,4-diones and 1,3-dimethyl-7-aryl-6-phenyl-(4-halophenyl)-1H-pyrido[2,3-d]pyrimidine-2,4-diones. The effect of the synthesized compounds on in vitro tumor DNA methylation was studied.