Results: Successfully synthesized the new chiral derivatives N-heptyl and N-benzyl cis (+); cis (-) - 4 - (3, 4-dimethoxyphenyl) hexahydro phthalazinone with potential biological activities. Conclusions: The optical resolution of racemic carboxylic acid gave chiral of carboxylic acids with high optical purity by using R) - (+) and (S) - (-) - α-methylbenzylamine, which are pure chiral bases.