Process for preparing pyrido[2,3-d]pyrimidin-7-one and 3,4-dihydropyrimido[4,5-d]pyrimidin-2(1H)-one derivatives, and their precursors

摘要

Disclosed is a fused pyrimidine derivative of formula (II) or (IIa), wherein each G is carbon or nitrogen, Rg is alkyl, and wherein the other substituents are as defined in the specification. Also disclosed is a process for preparing the above compound from aldehyde-substituted pyrimidine intermediates.