| abstract |
(57) [Summary] [PROBLEMS] A conventional production method in which an amino acid, an acid, and an alcohol are contacted at one time cannot avoid the by-product, In addition, the present invention provides a method for producing a salt of an amino acid ester and an acid without by-producing "a salt of an N-alkyl-amino acid ester and an acid" which is difficult to remove. SOLUTION: An amino acid is brought into contact with an acid to convert the amino acid into a form of a salt of the amino acid and the acid once, and if necessary, a dehydration treatment is carried out. A salt of the reactive amino acid ester and the acid is produced below. |