申请人:Mitsui Toatsu Chemicals, Incorporated
公开号:US04801732A1
公开(公告)日:1989-01-31
This invention relates to an improved process for preparing .alpha.-L-aspartyl-L-phenylalanine methyl ester. More specifically, it relates to a process for preparing .alpha.-L-aspartyl-L-phenylalanine methyl ester which comprises treating, as a raw material, N-formyl-.alpha.-L-aspartyl-L-phenylalanine in methanol in the presence of an acid to form .alpha.-L-aspartyl-L-phenylalanine dimethyl ester, hydrolyzing the .alpha.-L-aspartyl-L-phenylalanine dimethyl ester by bringing it into contact with hydrochloric acid in the presence of methanol as desired, separating the thereby-precipitated .alpha.-L-aspartyl-L-phenylalanine methyl ester hydrochloride and neutralizing the hydrochloride. Further, this invention also provides a process for preparing .alpha.-L-aspartyl-L-phenylalanine methyl ester capable of using, as a raw material, N-formyl-.alpha.-L-aspartyl-L-phenylalanine which contains N-formyl-.beta.-L-aspartyl-L-phenylalanine in an amount of 30% by weight or less.
这项发明涉及一种改进的制备α-L-天冬氨酸-L-苯丙氨酸甲酯的过程。更具体地说,它涉及一种制备α-L-天冬氨酸-L-苯丙氨酸甲酯的方法,包括在存在酸的情况下,用N-甲酰-α-L-天冬氨酸-L-苯丙氨酸在甲醇中处理以形成α-L-天冬氨酸-L-苯丙氨酸二甲酯,通过将α-L-天冬氨酸-L-苯丙氨酸二甲酯与盐酸在甲醇存在的情况下接触以水解α-L-天冬氨酸-L-苯丙氨酸二甲酯,分离由此沉淀的α-L-天冬氨酸-L-苯丙氨酸甲酯盐酸盐并对盐酸盐进行中和。此外,这项发明还提供了一种制备α-L-天冬氨酸-L-苯丙氨酸甲酯的方法,可使用含有N-甲酰-β-L-天冬氨酸-L-苯丙氨酸不超过30%重量的N-甲酰-α-L-天冬氨酸-L-苯丙氨酸作为原料。