A library of novel 1 H-pyrimido [4, 5-c] pyridazine-5, 7-dione analogs was prepared in a parallel fashion via the cyclization of 6-(1-ethylhydrazinyl)-3-methylpyrimidine-2, 4 (1H, 3H)- dione (4) with α-bromoketones and was then isolated by a two-step purification method with> 90% purity. Both the library synthesis and purification method proved suitable for analogs with a high diversity of substitution at the 3-position including various alkyl, aryl, ...
