Novel pyrimidine derivatives by sonication and traditional thermal methods

A series of bis-compounds (2) were synthesized by condensing dihydro-1,3-(disubstituted)phenyl-2-thioxopyrimidine-4,6(1H,5H)-dione with hippuric acid in presence of acetic anhydride. The compound (2) on further treatment with aromatic amine afforded dihydropyrimidine (3) through an eco-friendly procedure by sonication. The sonication method reduces time and gives higher yields, and also the effluent produced is free from hazardous contamination and organic by-products. The novel pyrimidines were also synthesized by traditional methods for comparison purposes and sonication method was found to be superior. Structures of the synthesized compounds have been elucidated on the basis of elemental analysis and spectral data.