Patent ID: 6245934
Filing Date: 2001-06-12
Classification: A23L,C07K,Y02P

Abstract:
A method for preparing a salt of aspartylphenylalanine methyl ester from N-protected aspartylphenylalanine methyl ester involving cleaving off the protective group by treatment with an acid comprising:a) reacting N-protected aspartylphenylalanine methyl ester, in an aqueous medium and in the presence of methanol at a temperature of from 0 to 80.degree. C., with from 0.8 to 2 equivalents of acesulphamic acid for at least such a time that the conversion to the salt of aspartylphenylalanine methyl ester and acesulphamic acid has been completed to an adequate degree, andb) precipitating the salt formed in step (a) at a temperature of 30.degree. C. or lower.