Method for crystallizing alpha-L-aspartyl-L-phenylalanine methyl ester.

摘要

A method for crystallizing alpha -L-aspartyl-L-phenylalanine methyl ester which comprise mixing hot aqueous solution containing alpha -L-aspartyl-L-phenylalanine methyl ester and a cold aqueous solution which may contain alpha -L-aspartyl-L-phenylalanine methyl ester, in such proportions that the concentration of alpha -L-aspartyl-L-phenylalanine methyl ester after mixing exceeds its solubility in the mixture of the two aqueous solutions at the temperature of the mixture, to precipitate crystals of alpha -L-aspartyl-L-phenylalanine methyl ester, and if necessary, cooling the mixture, the total amount of alpha -L-aspartyl-L-phenylalanine methyl ester contained in the hot and cold aqueous solutions being such that when the two aqueous solutions are mixed to precipitate crystals of alpha -L-aspartyl-L-phenylalanine methyl ester, it exceeds the solubility level of alpha -L-aspartyl-L-phenylalanine methyl ester in the mixture of the two aqueous solutions at the temperature of the mixture.