| abstract |
The present invention relates to a continuous process for preparing optically pure (S)-3,4-dihydroxybutyric acid derivatives expressed by the following Formula 1 and more particularly, to the continuous process which enables preparing optically pure (S)-3,4-dihydroxybutyric acid derivatives economically in large quantities, by:(a) Preparing alpha-(1,4) linked oligosaccharide having adequate sugar distribution by reacting amylopectin which is easily available from natural product with enzyme under a specific condition; and(b) Performing oxidatioin by running basic anion exchange resin with an oxidant to give (S)-3,4-dihydroxybutyric acid-anion exchange resin complex, dissociating the (S)-3,4-dihydroxybutyric acid from anion exchange resin complex and esterification sequentially under a specific condition. wherein Represents linear or branched alkyl group with 1~5 carbon atoms. |