Patents by Inventor Hiroaki Kitaoka

Hiroaki Kitaoka 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).

  • Patent number: 6552197
    Abstract: Disclosed are a process for the preparation of a compound represented by the formula (1), which comprises treating a compound represented by the formula (2) with methanesulfonic acid and then subjecting the thus-treated compound to recrystallization; and Compound (1) so obtained. This Compound (1) is free of hygroscopicity, excellent in filterability and solubility and easy in handling. Furthermore, according to the preparation process of the present invention, an unnecessary isomer can be converted into the target one and separation of the target isomer can be conducted easily.
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: April 22, 2003
    Assignees: Daiichi Pharmaceutical Co., Ltd., Kabushiki Kaisha Yakult Honsha
    Inventors: Shinji Kamihara, Kazuaki Kanai, Shigeru Noguchi, Hirofumi Terasawa, Hiroaki Kitaoka
  • Patent number: 6504029
    Abstract: Disclosed are a process for the preparation of a compound represented by the formula (1), which comprises treating a compound represented by the formula (2) with methanesulfonic acid and then subjecting the thus-treated compound to recrystallization; and Compound (1) so obtained. This Compound (1) is free of hygroscopicity, excellent in filterability and solubility and easy in handling. Furthermore, according to the preparation process of the present invention, an unnecessary isomer can be converted into the target one and separation of the target isomer can be conducted easily.
    Type: Grant
    Filed: July 13, 1995
    Date of Patent: January 7, 2003
    Assignee: Daiichi Pharmaceutical Co., Ltd.
    Inventors: Shinji Kamihara, Kazuaki Kanai, Shigeru Noguchi, Hirofumi Terasawa, Hiroaki Kitaoka
  • Publication number: 20010034446
    Abstract: Disclosed are a process for the preparation of a compound represented by the formula (1), which comprises treating a compound represented by the formula (2) with methanesulfonic acid and then subjecting the thus-treated compound to recrystallization; and Compound (1) so obtained.
    Type: Application
    Filed: June 11, 2001
    Publication date: October 25, 2001
    Applicant: DAIICHI PHARMACEUTICAL CO., LTD.
    Inventors: Shinji Kaminhara, Kazuaki Kanai, Shigeru Noguchi, Hirofumi Terasawa, Hiroaki Kitaoka
  • Patent number: 6169108
    Abstract: An anhydrous crystal of a compound represented by the formula: R2—CH2CONH—R1 wherein R1 represents a substituted or non-substituted pyridyl group or substituted or non-substituted phenyl group and R2 represents a substituted or non-substituted 2-oxo-1-pyrrolidinyl group, characterized in that said crystal is substantially free from hygroscopicity. For example, by drying a hydrous crystal of said compound at a temperature of 80° C. or above under reduced pressure, an anhydrous crystal is provided that exhibits a weight increase of 1% or less when stored under the relative humidity of 83% at the temperature of 25° C. for 30 days. By using the anhydrous crystal for the manufacture of a medicament comprising the compound as an active ingredient, a product with a constant content of the active ingredient can be obtained.
    Type: Grant
    Filed: November 7, 1997
    Date of Patent: January 2, 2001
    Assignee: Daiichi Pharmaceutical Co., Ltd.
    Inventors: Yukio Sato, Hiroaki Kitaoka, Tatsuya Terada, Makoto Ono
  • Patent number: 5948913
    Abstract: Crystals of 3-?2-?4-(3-chloro-2-methylphenyl)-1-piperazinyl!ethyl!-5,6-dimethoxy-1-(4- imidazolylmethyl)-1H-indazole dihydrochloride which is a hydrate for pharmaceutical use having excellent characteristics as a pharmaceutical material that has high storage stability and which substantially has specified X-ray diffraction characteristics, more particularly, the dihydrochloride is 3.5-hydrate.
    Type: Grant
    Filed: May 14, 1997
    Date of Patent: September 7, 1999
    Assignee: Daiichi Pharmaceutical Co., Ltd.
    Inventors: Kenjiro Yamamoto, Akihiko Miyadera, Hiroaki Kitaoka