申请人:Nitrokemia Ipartelepek
公开号:US05639905A1
公开(公告)日:1997-06-17
Process for the preparation of N-phenyl-N-methoxyacetyl-DL-alanine methyl ester derivatives of the formula (I). ##STR1## wherein R is a C.sub.1-4 alkyl residue; and n is a cardinal number between from 1 to 3, which comprises reacting an N-methoxyacetyl derivative of the formula (II). ##STR2## wherein R and n are as defined above, with a stoichiometric amount of an alkaline metal alkoxide, at a temperature between 80.degree. C. and 150.degree. C., until completion of the removal of the alkanol present in the system, then reacting the thus obtained alkaline metal salt of the compound of formula (II) directly or after isolation with a methyl DL-x-halopropionate.
制备公式(I)中的N-苯基-N-甲氧基乙酰-DL-丙氨酸甲酯衍生物的过程如下:其中R为C.sub.1-4烷基残基;n为介于1至3之间的基数。首先将公式(II)中的N-甲氧基乙酰衍生物与碱性金属烷氧化物按化学计量比反应,在80℃至150℃的温度下反应,直到完全去除体系中的烷醇,然后将所得的公式(II)化合物的碱性金属盐直接或经过分离后与甲基DL-x-卤代丙酸酯反应。