METHOD FOR PREPARING -L-ASPARTYL-L-PHENYLALANINE METHYL ESTER

摘要

A method for preparing .alpha.-L-aspartyl-L-phenylalanine methyl ester (.alpha.-APM), substantially free from acid ion contamination, is disclosed which comprises the steps of contacting a solution of a mineral acid salt or an organic sulfonic acid salt of .alpha.-APM in an aqueous solvent with an anion exchange resin in free base form, separating the resin from the thus-produced solution of .alpha.-APM; and isolating the .alpha.-APM therefrom, preferably with regeneration and recycling the resin.