A new approach to the synthesis of Biginelli compounds

A new synthesis of 4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylic acid esters is based on the reactions of α-tosyl-substituted phenyl carbamates with the enolates of β-oxoesters followed by treatment with ammonia and dehydration of the resulting 4-hydroxyhexahydropyrimidin-2-ones.