Method for optical resolution of racemic 6-(4-aminophenyl)- 4,5dihydro-5-methyl-3(2H)-pyridazinone to enantiomers

摘要

A method for the optical resolution of racemic 6-(4-aminophenyl)-4,5dihydro-5-methyl-3(2H)-pyridazinone to enantiomers which method comprises the following steps: a) contacting the racemic mixture with D- or L-tartaric acid in ethyl acetate solvent; b) recovering the crystalline salt therefrom; and c) optionally basifying the salt to form the corresponding free base.