A convenient synthesis of novel pyrimidine analogues of o-hydroxy chalcones and pyrano [2,3-d]pyrimidines and their biological activities

A convenient method for the synthesis of new pyrimidine analogues of chalco nes by condensation of 5-acetyl-1,3-diaryl-1,2,3,4-tetrahydro-6-hydroxy-4-o xo-2-thioxopyrimidines with aromatic aldehydes in aqueous methanol ic potas sium hydroxide (method A) and by condensation of 1,3-diaryl-2-thiobarbituri c acids with cinnamoyl chlorides in presence of triethylamine (method B) is reported which on subsequent oxidative cyclization afforded 1,3,7-triaryl- 1,2,3,4-tetrahydro-4,5-dioxo-2-thioxo-5H-pyrano[2,3-d]pyrimidines which wer e evaluated for their antimicrobial activity.