3(2H)-Pyridazinone, 6-(4-amino-3,5-dimethyl-1H-pyrazol-1-yl)-, hydrazone, dihydrochloride 3-Hydrazino-6-(3,5-dimethyl-4-amino-1-pyrazolyl)pyridazine dihydrochloride 6-(4-Amino-3,5-dimethyl-1H-pyrazol-1-yl)-3(2H)-pyridazinone hydrazone dihydrochloride 70589-21-8