Synthesis and some properties of dyes containing the pyrano[2,3-d]-pyrimidine nucleus
Abstract
The condensation of 1,3-dialkylbarbituric acids with ethyl orthoacetate gives 7H-pyrano[2,3-d]pyrimidines. The structures of these dyes were confirmed by their reactions. The preparation and light absorptions of several non-ionic trinuclear dyes containing the pyrano[2,3-d]pyrimidine nucleus are discussed.