Patents by Inventor Takeshi Tsubuki

Takeshi Tsubuki 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: 9315453
    Abstract: [Problem] For example, 4-(3-benzyloxyphenylthio)-2-chloro-1-(3-nitropropyl)benzene (compound 1) is used as an intermediate for producing a 2-amino-2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-1,3-propanediol hydrochloride which has excellent immunosuppressive activity. This compound 1 is traditionally obtained only as an oil and thus handling and refining were difficult. [Solution] A crystal of the compound 1 is obtained. A method of crystallizing the same is also established. Furthermore, a simple refining method is also found which comprises stirring in suspension the crystal in a solvent. Since the compound 1 can be obtained as a crystal, it is easier to handle and long term storage is possible.
    Type: Grant
    Filed: April 17, 2013
    Date of Patent: April 19, 2016
    Assignee: KYORIN PHARMACEUTICAL CO., LTD.
    Inventors: Takeshi Tsubuki, Hiroya Sato
  • Publication number: 20150073178
    Abstract: [Problem] For example, 4-(3-benzyloxyphenylthio)-2-chloro-1-(3-nitropropyl)benzene (compound 1) is used as an intermediate for producing a 2-amino-2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-1,3-propanediol hydrochloride which has excellent immunosuppressive activity. This compound 1 is traditionally obtained only as an oil and thus handling and refining were difficult. [Solution] A crystal of the compound 1 is obtained. A method of crystallizing the same is also established. Furthermore, a simple refining method is also found which comprises stirring in suspension the crystal in a solvent. Since the compound 1 can be obtained as a crystal, it is easier to handle and long term storage is possible.
    Type: Application
    Filed: April 17, 2013
    Publication date: March 12, 2015
    Inventors: Takeshi Tsubuki, Hiroya Sato
  • Publication number: 20130317214
    Abstract: [Problem] To efficiently (without carrying out column purification) provide a high-purity maleate having excellent storage stability, solubility, crystallinity and ease of handling according to the present invention. [Solution] This method for producing the maleate represented by formula (1) includes obtaining the compound represented by formula (2) by reacting the compound represented by formula (3) with the compound represented by formula (4) in the presence of a salt, precipitating crystals of the compound represented by formula (2) by mixing the obtained compound represented by formula (2) with acetone and water, and obtaining the maleate represented by formula (1) by adding maleic acid to an acetone solution of the compound represented by formula (2), prepared by dissolving the crystals of the obtained compound represented by formula (2) in acetone.
    Type: Application
    Filed: November 30, 2011
    Publication date: November 28, 2013
    Applicant: KYORIN PHARMACEUTICAL CO., LTD.
    Inventor: Takeshi Tsubuki
  • Publication number: 20130317215
    Abstract: [Problem] To provide a stable industrially-manufactured intermediate, enabling an industrially stable supply of 2-pyridyl-benz[d][1,3]oxazine to be provided. [Solution] The compound represented by formula (6) (wherein M represents sodium or potassium).
    Type: Application
    Filed: November 30, 2011
    Publication date: November 28, 2013
    Applicant: KYORIN PHARMACEUTICAL CO., LTD.
    Inventors: Takeshi Tsubuki, Takahiro Tanase, Masashi Suzuki
  • Publication number: 20120245346
    Abstract: Disclosed is a benz[d][1,3]oxazine derivative having excellent stability when used as an active ingredient for a medicinal agent, and also having excellent solubility and crystallinity. Specifically disclosed is 2-[2-((S)-3-dimethylaminopyrrolidin-1-yl)pyridin-3-yl]-5-ethyl-7-methoxy-4H-benz[d][1,3]oxazin-4-one maleate.
    Type: Application
    Filed: September 27, 2010
    Publication date: September 27, 2012
    Applicant: Kyorin Pharmaceutical Co., Ltd.
    Inventors: Takeshi Tsubuki, Tetsuya Sagawa, Keiko Funada, Ichiro Araya
  • Publication number: 20110077427
    Abstract: Disclosed is a preparation method which makes it possible to produce an aminoalcohol derivative having a high optical purity and to enable the large scale synthesis thereof at a low price. For instance, a compound represented by the following general formula (8) is recrystallized in the course of the production process thereof: In this case, R1 represents, for instance, a trihalomethyl group; R2 represents, for instance, a hydrogen atom; R3 represents, for instance, a halogen atom; R4 represents, for instance, a lower alkyl group; X represents, for instance, a sulfur atom; n represents an integer ranging from 1 to 4; and W represents hydrogen chloride or hydrogen bromide.
    Type: Application
    Filed: May 19, 2009
    Publication date: March 31, 2011
    Applicant: Kyorin Pharmaceutical Co., Ltd.
    Inventors: Takeshi Tsubuki, Ichiro Araya, Takahiro Kanda, Shintaro Kanazawa
  • Patent number: 7795472
    Abstract: A process for the industrial production of 2-amino-2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-1,3-propanediol hydrochloride (Compound I), an effective immunosuppressant. The process for producing 2-amino-2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-1,3-propanediol hydrochloride or a hydrate thereof includes the steps of reacting 4-(3-benzyloxyphenylthio)-2-chlorobenzaldehyde with ethyl diethylphosphonoacetate in a solvent in the presence of a base to form ethyl 3-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]acrylate; reducing the resulting ethyl 3-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]acrylate, followed by mesylation, iodination and nitration, to form 1-benzyloxy-3-[3-chloro-4-(3-nitropropyl)phenylthio]benzene; forming 2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-2-nitro-1,3-propanediol using a formaldehyde solution; and reducing the resulting 2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-2-nitro-1,3-propanediol to form the desired product.
    Type: Grant
    Filed: October 7, 2005
    Date of Patent: September 14, 2010
    Assignee: Kyorin Pharmaceutical Co., Ltd.
    Inventors: Takeshi Tsubuki, Kenichi Kobayashi, Hidetaka Komatsu
  • Publication number: 20080207941
    Abstract: A process for the industrial production of 2-amino-2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-1,3-propanediol hydrochloride (Compound I), an effective immunosuppressant. The process for producing 2-amino-2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-1,3-propanediol hydrochloride or a hydrate thereof includes the steps of reacting 4-(3-benzyloxyphenylthio)-2-chlorobenzaldehyde with ethyl diethylphosphonoacetate in a solvent in the presence of a base to form ethyl 3-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]acrylate; reducing the resulting ethyl 3-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]acrylate, followed by mesylation, iodination and nitration, to form 1-benzyloxy-3-[3-chloro-4-(3-nitropropyl)phenylthio]benzene; forming 2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-2-nitro-1,3-propanediol using a formaldehyde solution; and reducing the resulting 2-[2-[4-(3-benzyloxyphenylthio)-2-chlorophenyl]ethyl]-2-nitro-1,3-propanediol to form the desired product.
    Type: Application
    Filed: October 7, 2005
    Publication date: August 28, 2008
    Applicant: KYORIN PHARMACEUTICAL CO., LTD.
    Inventors: Takeshi Tsubuki, Kenichi Kobayashi, Hidetaka Komatsu