Abstract: A method of preparing optically pure (S)-3-hydroxypyrrolidine is disclosed. The present invention provides a method of economically and industrially preparing optically and chemically pure (S)-3-hydroxypyrrolidine, through a process comprising introducing an amine protecting group by using optically pure 4-amino-(S)-2-hydroxybutylic acid as a starting material, reducing a carboxylic acid group into a primary alcohol, removing the amine protecting group to form an amine salt, halogenating the primary alcohol, and amine cyclization; and through a simple purification process, i.e., distillation under reduced pressure. As another method, the present invention provides a method of preparing optically and chemically pure (S)-3-hydroxypyrrolidine, through a process comprising esterifying optically pure 4-amino-(S)-2-hydroxybutylic acid as a starting material, lactam cyclization, and reduction.

Abstract: A method of preparing optically pure (S)-3-hydroxypyrrolidine is disclosed. The present invention provides a method of economically and industrially preparing optically and chemically pure (S)-3-hydroxypyrrolidine, through a process comprising introducing an amine protecting group by using optically pure 4-amino-(S)-2-hydroxybutylic acid as a starting material, reducing a carboxylic acid group into a primary alcohol, removing the amine protecting group to form an amine salt, halogenating the primary alcohol, and amine cyclization; and through a simple purification process, i.e., distillation under reduced pressure. As another method, the present invention provides a method of preparing optically and chemically pure (S)-3-hydroxypyrrolidine, through a process comprising esterifying optically pure 4-amino-(S)-2-hydroxybutylic acid as a starting material, lactam cyclization, and reduction.

Abstract: The present invention relates to a process for preparing optically pure (S)-3-hydroxy-&ggr;-butyrolactone expressed by the following Formula 1 and more particularly, to a process that enables preparing optically pure (S)-3-hydroxy-&ggr;-butyrolactone economically in large quantities, by: (a) Preparing &agr;-(1,4) linked oligosaccharide with adequate sugar distribution by reacting starch which is easily available from natural product with enzyme under a specific condition; and (b) Performing oxidation and cyclization sequentially under a specific condition.

Abstract: The present invention relates to a process for preparing (R)-4-cyano-3-hydroxybutyric acid ester derivatives and more particularly, to a process for preparing optically pure (R)-4-cyano-3-hydroxybutyric acid ester derivatives expressed by formula (1) in high yield by performing cyanation and sequential esterification of (S)-3,4-epoxybutyric acid salt as a starting material. In said formula, R represents linear or branched alkyl group with 1˜5 carbon atoms or benzyl group.

Abstract: A process for the preparation of chiral (S)-2,3-disubstituted-1-propylamine derivatives, in which a carbonyl group of (S) 3,4-disubstituted-1-butanecarbonyl derivatives is converted to an amine group, and the conversion reaction is performed through Curtius rearrangement or Hoffman rearrangement.

Abstract: The present invention relates to a process for preparing optically pure (S)-3-hydroxy-&ggr;-butyrolactone expressed by the following Formula 1 and more particularly, to a process that enables preparing optically pure (S)-3-hydroxy-&ggr;-butyrolactone economically in large quantities, by:

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 &agr;-(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.

Abstract: The present invention relates to a continuous process for preparing optically pure (S)-3-hydroxy-&ggr;-butyrolactone expressed by the following Formula 1 and more particularly, to a process which enables preparing optically pure (S)-3-hydroxy-&ggr;-butyrolactone economically in large quantities, by: (a) Preparing &agr;-(1,4) linked oligosaccharide with adequate sugar distribution by reacting amylopectin which is easily available from natural product with enzyme under a specific condition; and (b) Performing oxidation, esterification and cyclization sequentially under a specific condition.

Abstract: The present invention relates to a process for preparing optically pure (S)-3,4-dihydroxybutyric acid derivatives expressed by the following Formula 1 and more particularly, to a process that enables preparing optically pure (S)-3,4-dihydroxybutyric acid derivatives economically in large quantities, by: (a) Preparing &agr;-(1,4)-linked oligosaccharide with adequate sugar distribution by reacting amylopectin which is easily available from natural product with enzyme under a specific condition; and (b) Performing oxidation and esterification sequentially under a specific condition. wherein, R represents linear or branched alkyl group with 1˜5 carbon atoms.

Abstract: The present invention relates to a process for preparing optically pure (S)-3-hydroxy-.gamma.-butyrolactone expressed by the following Formula 1 and more particularly, to a process that enables preparing optically pure (S)-3-hydroxy-.gamma.-butyrolactone economically in large quantities, by:(a) Preparing .alpha.-(1,4) linked oligosaccharide with adequate sugar distribution by reacting amylopectin which is easily available from natural product with enzyme under a specific condition; and(b) Performing oxidation, esterification and cyclization sequentially under a specific condition.