Patents by Inventor Sadayuki Maeda

Sadayuki Maeda 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: 9174899
    Abstract: A method is provided for producing optically active alcohols from ketones by reducing a ketone in the presence of an iridium(III) complex having a chiral prolinamide compound as a ligand.
    Type: Grant
    Filed: October 24, 2012
    Date of Patent: November 3, 2015
    Assignee: HAMARI CHEMICALS, LTD.
    Inventors: Sadayuki Maeda, Tatsunori Sato
  • Patent number: 9108986
    Abstract: Provided are a novel chiral iridium(III) complex; and a method for producing optically active 2-substituted-1,2,3,4-tetrahydroquinolines from 2-substituted-quinolines with the use of the chiral iridium(III) complex through a more economical and easy production process.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: August 18, 2015
    Assignee: HAMARI CHEMICALS, LTD.
    Inventors: Sadayuki Maeda, Tatsunori Sato, Yasuhiko Kawano, Toshio Miyawaki
  • Publication number: 20140296584
    Abstract: A method is provided for producing optically active alcohols from ketones by reducing a ketone in the presence of an iridium(III) complex having a chiral prolinamide compound as a ligand.
    Type: Application
    Filed: October 24, 2012
    Publication date: October 2, 2014
    Inventors: Sadayuki Maeda, Tatsunori Sato
  • Publication number: 20140228572
    Abstract: Provided are a novel chiral iridium(III) complex; and a method for producing optically active 2-substituted-1,2,3,4-tetrahydroquinolines from 2-substituted-quinolines with the use of the chiral iridium(III) complex through a more economical and easy production process.
    Type: Application
    Filed: July 13, 2012
    Publication date: August 14, 2014
    Applicant: HAMARI CHEMICALS, LTD.
    Inventors: Sadayuki Maeda, Tatsunori Sato, Yasuhiko Kawano, Toshio Miyawaki
  • Patent number: 8222452
    Abstract: The present invention provides a method for producing chiral amines, comprising asymmetric transfer hydrogenation of imine compounds in the presence of a hydrogen donor compound and an iridium(III) complex having a chiral prolinamide compound as a ligand. The present invention is useful for production of chiral amines in an efficient manner in terms of their optical and chemical yields.
    Type: Grant
    Filed: June 30, 2008
    Date of Patent: July 17, 2012
    Assignee: Hamari Chemicals, Ltd.
    Inventor: Sadayuki Maeda
  • Publication number: 20100160636
    Abstract: The present invention provides a method for producing chiral amines, comprising asymmetric transfer hydrogenation of imine compounds in the presence of a hydrogen donor compound and an iridium(III) complex having a chiral prolinamide compound as a ligand. The present invention is useful for production of chiral amines in an efficient manner in terms of their optical and chemical yields.
    Type: Application
    Filed: June 30, 2008
    Publication date: June 24, 2010
    Inventor: Sadayuki Maeda
  • Patent number: 4868312
    Abstract: N.sup..epsilon. -Trifluoroacetyl-L-lysyl-L-proline.D-10-camphorsulfonic acid salt is produced in very high purity by reacting N.sup..epsilon. -trifluoroacetyl-L-lysyl-L-proline with D-10-camphorsulfonic acid in a suitable solvent, followed by crystallization from the reaction mixture.The salt is extremely stable at a temperature of working ambience as compared with other salts of N.sup..epsilon. -trifluoroacetyl-L-lysyl-L-proline including known dicyclohexylamine salt of the same.
    Type: Grant
    Filed: May 26, 1988
    Date of Patent: September 19, 1989
    Assignee: Hamari Chemicals Ltd.
    Inventors: Sadayuki Maeda, Usao Nakamura, Makoto Sakanaka
  • Patent number: 4670607
    Abstract: A 2-(substituted aryl)propionaldehyde of the formula, ##STR1## (wherein Ar denotes ##STR2## is produced in high yield by reacting a methyl (substituted aryl) ketone of the formula ##STR3## with phenyldimethylsulfonium methylsulfate of the formula, ##STR4## in the presence of alkali metal hydroxide to obtain a reaction mixture containing 2-(substituted aryl)1,2-epoxypropane of the formula, ##STR5## and thioanisole, and subjecting the reaction mixture to contact with anhydrous MgCl.sub.2. The propionaldehyde compound is also produced in high yield by contacting the epoxypropane compound with anhydrous MgCl.sub.2 in the presence of a soft nucleophile such as a sulfide, a thiol and a phosphine.
    Type: Grant
    Filed: May 16, 1986
    Date of Patent: June 2, 1987
    Assignee: Hamari Chemicals, Ltd.
    Inventors: Sadayuki Maeda, Yasutaka Shinoo, Shinji Takenaka, Susumu Arashida, Iwao Shimizu
  • Patent number: 4490292
    Abstract: Novel 1,5-benzothiazepine derivatives having the formula; ##STR1## (wherein R.sub.1, R.sub.2 and R.sub.3 each denotes hydrogen, a halogen, a lower alkyl group, a lower alkoxy group or a hydroxy group; R.sub.4 denotes a lower alkyl group, an allyl group, a lower alkoxyalkyl group, a lower alkyl group substituted with a hydroxy group or a halogen, a lower alkylaminoalkyl group or a morpholino lower alkyl group; X denotes a halogen or hydrogen) are produced from corresponding 1,4-benzothiazine by a ring expansion reaction with trimethylhalosilane, hydrogen peroxide and water. The derivatives have analgesic, antipyretic and antiarrythmic activities.
    Type: Grant
    Filed: October 7, 1983
    Date of Patent: December 25, 1984
    Assignee: Hamari Chemicals, Ltd.
    Inventors: Yoshifumi Maki, Magoichi Sako, Naomichi Mitsumori, Sadayuki Maeda, Masahiro Takaya