Studies on Pyrimidine Derivatives. VII

Abstract

The product of the condensation of 5-amino-1, 2, 4-triazole (I) and diethyl ethoxy-methylenemalonate (II) was proved to be 6-ethoxycarbonyl-7-hydroxy-1, 2, 4-triazolo-[2, 3-α]pyrimidine (XI). Reaction of ethyl 2-cyano-3-ethoxyacrylate afforded 6-ethoxycarbonyl-7-amino-1, 2, 4-triazolo[2, 3-α]pyrimidine (XTV), 6-cyano-7-hydroxy-1, 2, 4-triazolo [2, 3-α]pyrimidine (XV), and ethyl 2-cyano-3-(1, 2, 4-triazol-5-ylamino) acrylate (XXI). 5-Hydroxy-6-ethoxycarbonyl-1, 2, 4-triazolo[4, 3-α]pyrimidine (X) and 5-hydroxy-6-cyano-1, 2, 4-triazolo [4, 3-α] pyrimidine (XX) were prepared and these were found to undergo isomerization on being heated to fusion, forming (XI) from (X) and (XV) from (XX).