Pyrimido[4,5-c]pyridazines. 6. Pyrimido[4,5-c]pyridazines and 1,2,4-triazines from reactions between 6-hydrazinopyrimidin-4(3H)-ones and vicinal dicarbonyl reagents
Pyrimido[4,5-c]pyridazines. 6. Pyrimido[4,5-c]pyridazines and 1,2,4-triazines from reactions between 6-hydrazinopyrimidin-4(3H)-ones and vicinal dicarbonyl reagents