| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an industrial method for producing N-carbobenzoxy amino acid ester crystal. SOLUTION: Crystal of an N-protecting group amino acid ester is brought into contact with a melt of an N-protecting group amino acid ester, which is obtained by reacting an N-protecting group amino acid with alcohol in the presence of an acid catalyst, at <= the melting point. In this case, the content of solvent in the melt is <=10%. The N-protecting group amino acid is N- carbobenzoxy-S-phenyl-L-cysteine.</p> |
