One-pot, three-component, catalyst-free synthesis of novel derivatives of pyrido-[2,3-d]pyrimidines under ultrasonic irradiations

Novel derivatives of pyrido-[2,3-d] pyrimidines were synthesized via an efficient and catalyst- free, one-pot, three-component reaction of 3-(1-methyl-1H-pyrrol-2-yl)-3-oxopropanenitrile, 6-amino-(ethylthio)pyrimidine-4(3H)-one, and arylaldehydes under ultrasonic irradiations. This practical method furnished the desired pyridopyrimidines in high yields (79–89%) and short reaction times (25–40 min).