Patents by Inventor Sang-Chul Lim

Sang-Chul Lim has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method for optically resolving a racemic &agr;-substituted heterocyclic carboxylic acid using enzyme
    Patent number: 6455302
    Abstract: Disclosed is a method for optically resolving a racemic &agr;-substituted heterocyclic carboxylic acid (&agr;-HCCA) by taking advantage of enantioselectivity of enzymes. &agr;-HCCA is reacted with alcohol to give a racemic &agr;-HCCA ester, which is then reacted with an enzyme with enantioselectivity, whereby either R-form or S-form of the racemate is hydrolyzed. Extraction with an organic solvent can obtain enantiomers of the &agr;-HCCA ester. The extracted enantiomeric &agr;-HCCA ester is converted to enantiomeric &agr;-HCCA by catalytic hydrogenation in an organic solution or by enzymatic hydrolysis in an aqueous solution. Thus, a racemic mixture of &agr;-HCCA can be optically resolved with high optical purity at high yields as well as at low cost.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: September 24, 2002
    Assignee: SK Corporation
    Inventors: Ki-Nam Uhm, Sang-Chul Lim, Jong-Ho Lim
  • Method for preparing an R- or S-form of &agr;-substituted heterocyclic carboxylic acid and a counter enantiomeric form of &agr;-substituted heterocyclic carboxylic acid ester thereto using enzyme
    Patent number: 6440721
    Abstract: Disclosed is a method for preparing an R- or S-forms of &agr;-substituted heterocyclic carboxylic acid (&agr;-HCCA) and a counter enantiomeric form of &agr;-substituted heterocyclic carboxylic acid ester thereto by use of an enzyme. A racemic &agr;-HCCA is reacted with alcohol to give a racemic &agr;-HCCA ester, which is then brought into contact with an enzyme with enantioselectivity, whereby either R-form or S-form of the racemate is hydrolyzed. Extraction with an organic solvent can obtain enantiomers of the &agr;-HCCA ester. Thus, a certain enantiomeric form of &agr;-HCCA and a counter enantiomeric form of &agr;-HCCA ester thereto, respectively can be prepared with high optical purity at high yields as well as at low cost.
    Type: Grant
    Filed: May 30, 2001
    Date of Patent: August 27, 2002
    Assignee: SK Corporation
    Inventors: Ki-Nam Uhm, Sang-Chul Lim, Jong-Ho Lim
  • Method for optically resolving a racemic alpha-substituted heterocyclic carboxylic acid using enzyme
    Publication number: 20020025565
    Abstract: Disclosed is a method for optically resolving a racemic &agr;-substituted heterocyclic carboxylic acid (&agr;-HCCA) by taking advantage of enantioselectivity of enzymes. &agr;-HCCA is reacted with alcohol to give a racemic &agr;-HCCA ester, which is then reacted with an enzyme with enantioselectivity, whereby either R-form or S-form of the racemate is hydrolyzed. Extraction with an organic solvent can obtain enantiomers of the &agr;-HCCA ester. The extracted enantiomeric &agr;-HCCA ester is converted to enantiomeric &agr;-HCCA by catalytic hydrogenation in an organic solution or by enzymatic hydrolysis in an aqueous solution. Thus, a racemic mixture of &agr;-HCCA can be optically resolved with high optical purity at high yields as well as at low cost.
    Type: Application
    Filed: May 31, 2001
    Publication date: February 28, 2002
    Inventors: Ki-Nam Uhm, Sang-Chul Lim, Jong-Ho Lim
  • Method for preparing an R- or S-form of alpha-substituted heterocyclic carboxylic acid and a counter enantiomeric form of alpha-substituted heterocyclic carboxylic acid ester thereto using enzyme
    Publication number: 20020006644
    Abstract: Disclosed is a method for preparing an R- or S-forms of &agr;-substituted heterocyclic carboxylic acid (&agr;-HCCA) and a counter enantiomeric form of &agr;-substituted heterocyclic carboxylic acid ester thereto by use of an enzyme. A racemic &agr;-HCCA is reacted with alcohol to give a racemic &agr;-HCCA ester, which is then brought into contact with an enzyme with enantioselectivity, whereby either R-form or S-form of the racemate is hydrolyzed. Extraction with an organic solvent can obtain enantiomers of the &agr;-HCCA ester. Thus, a certain enantiomeric form of &agr;-HCCA and a counter enantiomeric form of &agr;-HCCA ester thereto, respectively can be prepared with high optical purity at high yields as well as at low cost.
    Type: Application
    Filed: May 30, 2001
    Publication date: January 17, 2002
    Inventors: Ki-Nam Uhm, Sang-Chul Lim, Jong-Ho Lim
  • Polyether amino acid ester compounds, preparation method and use thereof
    Patent number: 6053955
    Abstract: The present invention relates to polyether amino acid ester compounds, preparation method and their use as hydrocarbon fuel additives.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: April 25, 2000
    Assignee: SK Corporation
    Inventors: Byung Hyung Lee, Woo Sun Kim, Sang Chul Lim, Ho Young Kwon, Dae Joon Yang