The multicomponent reactions between 6-aminouracil, aromatic aldehydes, and malononitrile to yield pyrido[2,3-d]-pyrimidine derivatives were carried out in glycerol as green solvent under microwave heating (Table 1). This method provided good to excellent yields for a variety of aldehydes with electron-withdrawing substituents on the aromatic ring. Lower yields were observed for some electron-donating aldehydes. This approach has some advantages in comparison to other methods reported in the literature including shorter reaction times, easy work-up procedure and absence of volatile organic solvents.