Patents by Inventor Kuniaki Nagaoka

Kuniaki Nagaoka 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).

  • Process for producing CMP-N-acetylneuraminic acid
    Patent number: 8450088
    Abstract: A method by which high-purity CMP-N-acetylneuraminic acid (HPLC purity, 95% or higher), which has been difficult to obtain with any technique other than chromatography, can be easily obtained in satisfactory yield by a simple operation without the need of chromatography. The process, which is for producing high-purity CMP-N-acetylneuraminic acid (CMP-NeuAc), is characterized by conducting a suitable combination of the following steps (1) to (4). Step 1: a step in which divalent cations are added to a solution containing CMP-NeuAc to thereby precipitate the phosphoric acid, pyrophosphoric acid, and nucleotide which coexist; Step 2: a step in which a phosphatase is added to a solution containing CMP-NeuAc to thereby convert the coexistent nucleotide into nucleoside; Step 3: a step in which an organic solvent is added to precipitate the CMP-NeuAc; and Step 4: a step in which the CMP-NeuAc precipitated is recovered.
    Type: Grant
    Filed: September 21, 2004
    Date of Patent: May 28, 2013
    Assignee: Yamasa Corporation
    Inventors: Tomoki Hamamoto, Kuniaki Nagaoka, Toshitada Noguchi
  • Process for Producing Cmp-N-Acetylneuraminic Acid
    Publication number: 20080070285
    Abstract: A method by which high-purity CMP-N-acetylneuraminic acid (HPLC purity, 95% or higher), which has been difficult to obtain with any technique other than chromatography, can be easily obtained in satisfactory yield by a simple operation without the need of chromatography. The process, which is for producing high-purity CMP-N-acetylneuraminic acid (CMP-NeuAc), is characterized by conducting a suitable combination of the following steps (1) to (4). Step 1: a step in which divalent cations are added to a solution containing CMP-NeuAc to thereby precipitate the phosphoric acid, pyrophosphoric acid, and nucleotide which coexist; Step 2: a step in which a phosphatase is added to a solution containing CMP-NeuAc to thereby convert the coexistent nucleotide into nucleoside; Step 3: a step in which an organic solvent is added to precipitate the CMP-NeuAc; and Step 4: a step in which the CMP-NeuAc precipitated is recovered.
    Type: Application
    Filed: September 21, 2004
    Publication date: March 20, 2008
    Inventors: Tomoki Hamamoto, Kuniaki Nagaoka, Toshitada Noguchi