Pyrimidines. 75. Syntheses based on acetylpyrimidines. 4,6-Dihydroxy-5-acetylpyrimidine and preparation of 4′,5-bipyrimidines and their derivatives

4,6-Dihydroxy-5-acetylpyrimidine was obtained by the solvolysis of 4,6-dialkoxy-5-acetylpyrimidines. The hydrolysis of 4,6-dichloro-5-acetylpyrimidine leads to opening of the heteroring to give s-cis,trans conformera of 2-cyano-3-hydroxy-2-buteneamide. 2,4,6-Trihydroxy[4,5]bipyrimidine was obtained by the condensation of 4,6-dialkoxy-5-acetylpyrimidines with benzalbisurea. It is shown that the products of the reaction of the same ketones with benzaldehyde in the presence of sodium alkoxides are derivatives of -diketones.See [1] for Communication 74.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 378–385, March, 1985.