Condensation of 2-ethoxymethylene-1, 3-dicarbonyl compounds with 5-aminopyrazole (I) was examined and several kinds of 6, 7-disubstituted pyrazolo [1, 5-a] pyrimidines were obtained. In the reaction of ethyl 2-cyano-3-ethoxyacrylate with (I), ethyl 2-cyano-3-(5-Dvrazolylamino) acrylate (II) as the intermediate was isolated.
