摘要:
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. ##STR1##
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
This invention relates to a process for manufacturing an optically active (S)-3,4-epoxybutyric acid salt and more particularly, to a method for manufacturing (S)-3,4-epoxybutyric acid salt expressed by the following formula 1, wherein an optically active (S)-3-hydroxybutyrolactone is employed to undergo an economical ring-opening reaction and epoxvdation so that its chiral center is maintained in an original form, Wherein, R1 represents alkali metal atom, alkaline earth metal atom, alkylamine group or quarternary amine group.
摘要:
The present invention relates to a composition for stimulating bone growth containing the extract of crude drug complex as an active ingredient. The extract of crude drug complex comprising Dipsaci radix, Astragalus membranaceus and Acanthopanax senticosus of the present invention stimulates bone growth, so that it can be effectively used for the composition and health food for stimulating bone growth.
摘要:
A tamper detection method and a data storage device using the same are provided. The tamper detection method includes sensing a value of pressure applied to a data storage device using a pressure sensor, comparing the sensed pressure value with an initial pressure value sensed at an initial operation time of the data storage device, and detecting malicious tamper by comparing a threshold pressure value varying with the number of loads applied to the data storage device when the sensed pressure value is smaller than the initial pressure value.