Patent ID: 8183413

Claim:
A process for production of a β-amino-α-hydroxy carboxamide derivative (1) of the following general formula (1); (wherein R represents an alkyl group having 1 to 6 carbon atoms and optionally having a substituent, or an aralkyl group having 7 to 15 carbon atoms and optionally having a substituent; P 1 and P 2 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms and optionally having a substituent, an aralkyl group having 7 to 15 carbon atoms and optionally having a substituent, or a carboxyl group; HX represents a mineral acid, a sulfonic acid, or a carboxylic acid) characterized in that the β-amino-α-hydroxy carboxamide derivative (1) is obtained as a crystal by a crystallization step using a solvent containing a protic solvent.