Studies on Pyrimidine Derivatives. I

Abstract

Boiling of 2-hydrazino-4-hydroxy-6-methylpyrimidine (VI) with formic acid for a short time afforded two kinds of crystals, one of m.p. 300° (decomp.) (B) and the other of m.p. 249-251° (C). The structure of 5-methyl-7-hydroxy-s-triazolo[4, 3-a]-pyrimidine (V) was assigned to (B) and 5-hydroxy-7-methyl-s-triazolo[4, 3-a]-pyrimidine (IV) to (C). (C) converts to crystals of m.p. 277-279° (A) on boilling it with formic acid for a long period or by its fusion, and the product (A) was found to be identical with the condensate of 5-amino-s-triazole (I) and ethyl acetoacetate. Bülow gave the structure of 5-methyl-7-hydroxy-s-triazolo [2, 3-a] pyrimidine (II) to (A) and Birr, (IV). The writer supports Bülow's structure.