Patents by Inventor Kenji Sakuratani

Kenji Sakuratani 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).

  • Publication number: 20210283269
    Abstract: A method for producing an antibody-drug conjugate in which a drug-linker represented by formula (1) (wherein A represents the connecting position to an antibody) is conjugated to the antibody via a thioether bond, wherein the method comprising the steps of: (i) reducing the antibody with a reducing agent; (ii) reacting a drug-linker intermediate with the antibody reduced in step (i); (iii) adding a reagent having a thiol group to react with the residual drug-linker intermediate in step (ii); and then (iv) removing by-products derived from the drug-linker intermediate through ultrafiltration using a buffer solution containing a salt consisting of a strong acid and a strong base, and a method for producing a pharmaceutical composition containing the antibody-drug conjugate.
    Type: Application
    Filed: July 24, 2019
    Publication date: September 16, 2021
    Applicant: DAIICHI SANKYO COMPANY, LIMITED
    Inventors: Tatsuya YAMAGUCHI, Kenji SAKURATANI
  • Patent number: 8735598
    Abstract: The present invention provides a method for producing a 1-biphenylmethylimidazole compound having superior angiotensin II receptor antagonistic activity, or an intermediate thereof. The present invention provides a method for producing a compound having the formula (5) (R1, Ra: H, an alkyl group) by oxidizing a compound having the formula (1) (Ra: H, an alkyl group) using an oxidizing agent in the presence of a radical initiation reagent, and then reacting with an ammonia-generating reagent and a compound having the formula R1CHO(R1: H, an alkyl group) or a compound having the formula R1C(ORb)3 (R1: H, an alkyl group; Rb: an alkyl group).
    Type: Grant
    Filed: June 8, 2009
    Date of Patent: May 27, 2014
    Assignee: Daiichi Sankyo Company, Limited
    Inventors: Koji Sato, Tsutomu Yagi, Kenji Sakuratani, Yuichiro Tani
  • Publication number: 20110092713
    Abstract: The present invention provides a method for producing a 1-biphenylmethylimidazole compound having superior angiotensin II receptor antagonistic activity, or an intermediate thereof. The present invention provides a method for producing a compound having the formula (5) (R1, Ra: H, an alkyl group) by oxidizing a compound having the formula (1) (Ra: H, an alkyl group) using an oxidizing agent in the presence of a radical initiation reagent, and then reacting with an ammonia-generating reagent and a compound having the formula R1CHO(R1: H, an alkyl group) or a compound having the formula R1C(ORb)3 (R1: H, an alkyl group; Rb: an alkyl group).
    Type: Application
    Filed: June 8, 2009
    Publication date: April 21, 2011
    Applicant: DAIICHI SANKYO COMPANY, LIMITED
    Inventors: Koji Sato, Tsutomu Yagi, Kenji Sakuratani, Yuichiro Tani
  • Patent number: 7875722
    Abstract: The present invention relates to a method for producing a quinolone compound having high antibacterial activity and high safety, at high yield and in a simple manner. A quinolonecarboxylic acid derivative (1) of interest is produced through a one-pot manner by reacting a compound (2) with a salt of a cyclic amine (3) and with a boron derivative in a solvent in the presence of a base.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: January 25, 2011
    Assignee: Daiichi Sankyo Company, Limited
    Inventors: Koji Sato, Kenji Sakuratani
  • Publication number: 20100063279
    Abstract: The present invention relates to a method for producing a quinolone compound having high antibacterial activity and high safety, at high yield and in a simple manner. A quinolonecarboxylic acid derivative (1) of interest is produced through a one-pot manner by reacting a compound (2) with a salt of a cyclic amine (3) and with a boron derivative in a solvent in the presence of a base.
    Type: Application
    Filed: September 30, 2009
    Publication date: March 11, 2010
    Applicant: DAIICHI SANKYO COMPANY, LIMITED
    Inventors: Koji SATO, Kenji Sakuratani
  • Publication number: 20090137600
    Abstract: A compound having an action of suppressing platelet aggregation is provided. This compound also exhibits excellent physical properties and oral absorbability. This compound is represented by formula (Ib): Its production method is also provided.
    Type: Application
    Filed: August 5, 2005
    Publication date: May 28, 2009
    Applicant: DAIICHI PHARMACEUTICAL CO., LTD.
    Inventors: Koji Sato, Syouko Yoshida, Tsutomu Yagi, Kenji Sakuratani
  • Patent number: 7199260
    Abstract: A method of producing 2-fluorocyclopropane-1-carboxylic acid ester, which comprise by allowing a compound represented by the following formula (1): wherein X represents a chlorine atom, a bromine atom or an iodine atom; and R1 represents an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, or an aralkyl group composed of an aryl group having 6 to 12 carbon atoms and an alkylene group having 1 to 6 carbon atoms; to react with a reducing agent in the presence of a phase transfer catalyst. According to the production method of the present invention, the reaction time of dehalogenation can be greatly shortened.
    Type: Grant
    Filed: January 7, 2004
    Date of Patent: April 3, 2007
    Assignee: Daiichi Pharmaceutical Co., Ltd.
    Inventors: Yuichiro Tani, Keiji Nakayama, Kenji Sakuratani, Koji Sato
  • Publication number: 20060052626
    Abstract: A method of producing 2-fluorocyclopropane-1-carboxylic acid ester, which comprise by allowing a compound represented by the following formula (1): wherein X represents a chlorine atom, a bromine atom or an iodine atom; and R1 represents an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, or an aralkyl group composed of an aryl group having 6 to 12 carbon atoms and an alkylene group having 1 to 6 carbon atoms; to react with a reducing agent in the presence of a phase transfer catalyst. According to the production method of the present invention, the reaction time of dehalogenation can be greatly shortened.
    Type: Application
    Filed: January 7, 2004
    Publication date: March 9, 2006
    Applicant: DAIICHI PHARMACEUTICAL CO., LTD.
    Inventors: Yuichiro Tani, Keiji Nakayama, Kenji Sakuratani, Koji Sato