Abstract: This invention relates to a method of preparing optically active ?-2-thienyl-alanine, and more particularly to a method of preparing optically active ?-2-thienyl-L-alanine or optically active ?-2-thienyl-D-alanine through an optical resolution reaction using chiral dibenzoyl tartaric acid or a derivative thereof as an optical resolving agent.

Abstract: This invention relates to a method of preparing D-arginine, and more particularly to a method of preparing D-arginine by optically resolving DL-arginine using D-3-bromocamphor-8-sulfonic acid or a salt thereof as an optical resolving agent.

Abstract: This invention relates to a method of preparing D-arginine, and more particularly to a method of preparing D-arginine by optically resolving DL-arginine using D-3-bromocamphor-8-sulfonic acid or a salt thereof as an optical resolving agent.

Abstract: This invention relates to a method of preparing optically active ?-2-thienyl-alanine, and more particularly to a method of preparing optically active ?-2-thienyl-L-alanine or optically active ?-2-thienyl-D-alanine through an optical resolution reaction using chiral dibenzoyl tartaric acid or a derivative thereof as an optical resolving agent.

Abstract: The present invention relates to compounds 1, 1a (S-enantiomer) and 1b (R-enantiomer) of the following formula 1, and a method for preparing the same. [formula 1] The novel compound of the formula 1 is used as an important intermediate for preparing compounds 6, 6a (S-enantiomer) and 6b (R-enantiomer) of the following formula 6, which are 2,2?-binaphthol-3-aldehyde derivatives. Also, the present invention provides a method for preparing the compound of formula 1 with a very safe method at low cost.

Abstract: The present invention relates to a method for easily preparing (2RS)-amino-(3S)-hydroxy-butyric acid, which is a chiral amino acid, in a high yield and a high purity using a chemical synthesis and enzymatic reduction reaction; an intermediate therefor; and a method for preparing the intermediate.

Abstract: The present disclosure relates to a t-butylketone binaphthol derivative and a method of preparing the same, the t-butylketone binaphthol derivative being a high-efficiency chiral extracting agent which has a very high chiral selectivity enabling to extract an amino acid from an aqueous solution phase to an organic layer and to facilitate its hydrolysis, and enabling a continuous reuse of the organic layer.

Abstract: Disclosed is a method of preparing D-arginine, wherein D-arginine is obtained by the optical resolution of DL-arginine using D-3-bromocamphor-10-sulfonic acid as an optical resolving agent.

Abstract: The present invention relates to a method for preparing enantiomerically pure compounds 1a and 1b of the following formula 1 from racemic compound 1 of the following formula 1. [formula 1] The compounds 1a and 1b of the above formula 1 respectively are important intermediates for a process for preparing the respective compounds 2a and 2b of the following formula 2, which are 2,2?-binaphthol-3-aldehyde derivatives. The following compounds 2a and 2b are useful for preparing enantiomerically pure amino acids. The present invention provides a method for preparing the above compounds 1a and 1b very conveniently and economically, and suitably for mass production.

Abstract: According to the present invention, a method is provided wherein a basic aqueous phase containing an optically active ?-amino acid is brought into contact with an organic phase containing a racemisation catalyst in the form of a copper metal complex of copper ions and an ?-amino acid and salicylaldehyde, in the presence of a phase transition catalyst, thereby subjecting the optically active ?-amino acid to racemisation. In the ?-amino acid racemisation method according to the present invention, the reaction conditions are mild and thus there is little ?-amino acid breakdown and the yield is high, the racemisation catalyst can be reused, the ?-amino acid resulting from the racemisation can easily be isolated and purified, and the racemisation method can be implemented in volume such that the invention is economic.

Abstract: According to the present invention, a method is provided wherein a basic aqueous phase containing an optically active ?-amino acid is brought into contact with an organic phase containing a racemisation catalyst in the form of a copper metal complex of copper ions and an ?-amino acid and salicylaldehyde, in the presence of a phase transition catalyst, thereby subjecting the optically active ?-amino acid to racemisation. In the ?-amino acid racemisation method according to the present invention, the reaction conditions are mild and thus there is little ?-amino acid breakdown and the yield is high, the racemisation catalyst can be reused, the ?-amino acid resulting from the racemisation can easily be isolated and purified, and the racemisation method can be implemented in volume such that the invention is economic.

Abstract: The present invention relates to a method for easily preparing (2RS)-amino-(3S)-hydroxy-butyric acid, which is a chiral amino acid, in a high yield and a high purity using a chemical synthesis and enzymatic reduction reaction; an intermediate therefor; and a method for preparing the intermediate.

Abstract: This invention relates to a method for obtaining optically pure amino acids, including optical resolution and optical conversion. This method significantly shortens the time taken for optical transformation, and enables the repeated use of an organic solution containing a enantioselective receptor, to thereby obtain optically pure amino acids in a simple and remarkably efficient manner, and to enable the very economical mass production of optically pure amino acids.

Abstract: The present invention relates to a method for preparing enantiomerically pure compounds 1a and 1b of the following formula 1 from racemic compound 1 of the following formula 1. [formula 1] The compounds 1a and 1b of the above formula 1 respectively are important intermediates for a process for preparing the respective compounds 2a and 2b of the following formula 2, which are 2,2?-binaphthol-3-aldehyde derivatives. The following compounds 2a and 2b are useful for preparing enantiomerically pure amino acids. The present invention provides a method for preparing the above compounds 1a and 1b very conveniently and economically, and suitably for mass production.

Abstract: The present invention relates to compounds 1, 1a (S-enantiomer) and 1b (R-enantiomer) of the following formula 1, and a method for preparing the same. [formula 1] The novel compound of the formula 1 is used as an important intermediate for preparing compounds 6, 6a (S-enantiomer) and 6b (R-enantiomer) of the following formula 6, which are 2,2?-binaphthol-3-aldehyde derivatives. Also, the present invention provides a method for preparing the compound of formula 1 with a very safe method at low cost.