To test the antibacterial activity, 2- or 4-[2-(5-nitro-2-furyl) vinyl] pyrimidines were synthesized by the condensation of 5-nitro-2-furaldehyde (Va) with the active methyl group of pyrimidines. It has been found that Va predominantly condensed with the 4-methyl group of 2, 4-dimethylpyrimidine and in the reaction of Va with 2, 4-dimethylpyrimidine containing a functional group in the 6-position, the active hydrogen reactivity between the 2-methyl group and 4-methyl group is affected by the presence of group in the 6-position : in 2, 4-dimethylpyrimidines substituted by the hydroxy, amino and alkoxy group in the 6-position, the 2-methyl group was founded to be more active, while in the ones substituted by the acetamido, dimethylamino and chloro group, the 4-methyl group was more reactive.