Synthesis and tuberculocidic activity of some 4-arylaminomethylene-3-methyl-1-(pyrimidin-2-yl)pyrazol-5(4H)-ones

4-Arylaminomethylene-3-methyl-1-(6-methyl-4-oxo-1,4-dihydropyrimidin-2-yl)pyrazol-5(4H)-ones were synthesized by a three-component reaction between the 6-methyl-2-(3-methyl-5-oxo-2,5-dihydropyrazol-1-yl)pyrimidin-4(1H)-one, triethoxymethane, and an aromatic amine. These compounds were found to exist as aminomethyleneketones regardless of the electronic effects of substituents in the aromatic fragments. The resulting compounds showed pronounced tuberculocidic activity.