Reactions of ethyl 4-amino-6-(ethoxycarbonylmethyl)-2-phenylpyrimidine-5-carboxylate with hydrazines

Abstract

New substituted 4,6-diamino-7-hydroxypyrido[4,3-d]pyrimidin-5(6H)-ones were synthe-sized by treatment of ethyl 4-amino-6-(ethoxycarbonylmethyl)-2-phenylpyrimidine-5-car-boxylic acid with hydrazine hydrate and phenylhydrazine. In the case of methylhydrazine, the reaction proceeded in an unusual way and afforded a product identified, relying on NMR data, as functionally substituted 8-(5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-7-ylidene)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine comprising two amineimide fragments. A diacetyl derivative of this compound was obtained.