PYRIDAZINONE HYDROCHLORIDE COMPOUND AND METHOD FOR PRODUCING THE SAME

摘要

The present invention relates to a 3/2-hydrochloride of 4-chloro-5-[3-(4-benzylpiperazin-1-yl) carbonylmethoxy-4-methoxybenzylamino]-3(2H)-pyridazinone, and also relates to a method for producing the 3/2-hydrochloride of 4-chloro-5-[3-(4-benzylpiperazin-1-yl)carbonylmethoxy-4-methoxy-4-methoxybenzylamino]-3(2H)-pyridazinone which comprises crystallizing in an alcohol type solvent or an alcohol type-ester type mixture solvent in the presence of hydrogen chloride and water.