Pyrimidine derivatives have occupied an important position in natural and synthetic organic
chemistry, due to their wide range of biological activities particularly in cancer and virus researches[1].
Herein we report a facile and improved protocol for preparation of pyrimidinone derivatives via threecomponent reaction of aldehydes, N-unsubstitutedamidines, and ethyl cyanoacetate under thermal aqueous
conditions in the presence of Bismuth nitrate pentahydrate as catalyst. (Scheme 1)