Synthesis of some new pyrimidine and pyridopyrimidine derivatives

摘要

The reaction of 2-formyl-3-(dimethylamino) propenenitrile 1 with substituted urea give 2-cyano-3-ureido-acrylate 2, which is cyclized under alkaline conditions to yield 5-formyl-4-amino-3-alkyl-2-oxo-pyrimjidine derivatives 3. Treatment of 3 with various substituted hydrazides furnish the corresponding hydrazones 4a-w. Further, the reaction of 3 with ethyl cyanoacetate in the presence of acetic acid afford desired pyridopyrimidine 5.