Process for the chemical separation of racemic modifications of - aminocarboxylic acid derivatives, and cinchonidine salt intermediates

摘要

Racemic Modifications of -aminocarboxylic acid derivatives, such as of -amino-4-hydroxyphenylacetic acid derivatives, are prepared reliably and more economically than in known processes by reacting the DL-form of the derivative in a solvent with cinchonidine, isolating the precipitated cinchonidine salt and hydrolyzing said salt.