酶法拆分(±)-N-(2,6-二甲苯基)-丙氨酸甲酯

用脂肪酶Candida rugosa lipase (CRL)拆分(±)-N-(2,6-二甲苯基)-丙氨酸甲酯, 并进一步优化反应条件. 结果表明, 在加入1 mmol N-(2,6-二甲苯基)-丙氨酸甲酯、100 mL的0.2 mol/L磷酸缓冲液中, CRL拆分该底物的最适反应条件为: pH 6.4, CRL脂酶250 mg, 聚乙二醇(PEG) 2 g, 转速160 r?min^－1, 温度 35 ℃. 其中酶量、温度对转化率影响较大. 反应后分离得R-(＋)-N-(2,6-二甲苯基)-丙氨酸甲酯. 它和酰氯反应可制备一系列旋光性N-酰基丙氨酸类杀菌剂.

Enzymatic Resolution of Methyl (±)-N-(2,6-Dimethylphenyl)alanine

An enzymatic method for the production of methyl R-(＋)-N-(2,6-dimethylphenyl)alanine has been developed. The process consists of the stereoselective hydrolysis of the racemic esters catalyzed by Candida rugosa lipase (CRL). The conversion and reaction speed were evaluated by some critical reaction parameters such as pH, temperature, enzyme concentration, subsidiary and stirring speed. Under the conditions of pH 6.4, 35 ℃, 250 mg of CRL, 2 g of polyethylene glycol (PEG) and 160 r?min^－1, the best results of reaction were obtained, which contained 1 mmol of methyl (±)-N-(2,6-dimethylphenyl)alanine as well as 100 mL of 0.2 mol/L phosphate buffer solution (PBS). Meanwhile, enzyme concentration and temperature were benefical for the hydrolysis of esters. In a word, methyl R-(＋)-N-(2,6-dimethylphenyl)alanine was separated from the reaction and op-tically active N-acylalanines were prepared.