酶法拆分D,L-苯丙氨酸制备D-苯丙氨酸

Preparation of D-Phenylalanine from D,L-Phenylalanine by Enzyme Resolution

在固定化青霉素酰化酶(IPA-750)存在下,通过N-苯乙酰-D,L-苯丙氨酸(2)的选择性水解完成了酶法拆分D,L-苯丙氨酸(1)制备D-苯丙氨酸(5)的过程。选择性水解的较适宜反应条件为:22.83g,m(2)∶m(IPA-750)=6∶1,pH7.0,于30℃反应5h,产物为N-苯乙酰-D-苯丙氨酸(4)和L-苯丙氨酸(3,收率63%,光学纯度99%)。4用6mol·L-1盐酸于120℃水解反应8h,经脱盐处理得5,收率67%,光学纯度91%。3在含醋酸酐的醋酸溶液中进行消旋化处理,得到100%消旋的1可继续进行下一轮酶法拆分。

D-Phenylalanine（5） was resolved from D,L-phenylalanine（1） by selective hydrolyzation of N-phenylacefic-D, L-phenylalanine （2） in the presence of immobiled penicillin enzyme acylase （IPA-750）. The hydrolyzation conditions at 30 ℃ for 5 h were as follows： 3 was 2.83 g, m（2） ： m（IPA-750） =6 ： 1, pH value of reaction system was 7.0. The product was N-phenylacetic-D-phenylalanine （4）. It was hydrolyzed at 120 ℃ for 8 h in solution of HCl（6 mol·L^-1） to form 5（yield 67%, optical purity 99%）, and L-phenylalanine（3）（yield 62.5%, optical purity 99%） which was turned 100% racemie 1 in Ac2O-AcOH.