Parallel Synthesis of Novel 3-Substituted 1-Ethyl-6-methylpyrimido[4,5-c]pyridazine-5,7(1H,6H)-dione Analogs

Abstract

A library of novel 1H-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, and heteroaryl groups.

Keywords:

• Cyclization
• 6-(1-ethylhydrazinyl)-3-methylpyrimidine-2,4(1H,3H)-dione
• parallel synthesis
• 1H-pyrimido[4,5-c]pyridazine-5,7-dione analogs

ACKNOWLEDGMENT

We thank Dr. Linyi Wei for his helpful suggestion on intermediate synthesis.