Patents by Inventor Nobuo Ikekawa

Nobuo Ikekawa 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: 4588528
    Abstract: The invention provides new derivatives of vitamin D.sub.3 and specifically (22E,24R)-1,24-dihydroxy-.DELTA..sup.22 -vitamin D.sub.3 and (22E,24S)-1,24-dihdroxy-.DELTA..sup.22 -vitamin D.sub.3.The compounds exhibit vitamin D-like activity in their ability to stimulate intestinal calcium transport, increase serum inorganic phosphorous and mineralize bone indication ready application of the compounds in the treatment of various metabolic bone diseases. The characteristic of the compounds to not mobilize bone indicates that the compositions would find ready application in combination with vitamin D and various of its derivatives to achieve controlled bone mineralization.
    Type: Grant
    Filed: May 31, 1984
    Date of Patent: May 13, 1986
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Nobuo Ikekawa, Yoko Tanaka
  • Patent number: 4564474
    Abstract: The invention provides new derivatives of vitamin D, 23,23-difluoro-25-hydroxycholecalciferol and the acylates thereof, a method for preparing said compounds and various new intermediates utilized in such process.The derivative compounds are characterized by vitamin D-like activity as evidenced by their ability to increase intestinal calcium transport and serum calcium. The compounds are further characterized by resistance to hydroxylation at C-23, which is recognized as an essential metabolic step to the inactivation of vitamin D. The compounds should, therefore, provide vitamin D-like activity of greater time duration.
    Type: Grant
    Filed: August 13, 1984
    Date of Patent: January 14, 1986
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Yoko Tanaka, Nobuo Ikekawa, Yoshiro Kobayashi
  • Patent number: 4552698
    Abstract: The invention provides new derivatives of vitamin D, 23,23-difluoro-1,25-dihydroxycholecalciferol and the acylates thereof.The derivative compounds are characterized by vitamin D-like activity.
    Type: Grant
    Filed: August 13, 1984
    Date of Patent: November 12, 1985
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Yoko Tanaka, Nobuo Ikekawa, Yoshiro Kobayashi
  • Patent number: 4502991
    Abstract: The invention provides a new derivative of vitamin D, 23,23-difluoro-1,25-dihydroxycholecalciferol.The compound is characterized by vitamin D-like activity as evidenced by its ability to increase intestinal calcium transport. It is further characterized by its resistance to hydroxylation at C-23, which is recognized as an essential metabolic step to the inactivation of vitamin D, and therefore should provide vitamin D-like activity of greater time duration.
    Type: Grant
    Filed: August 18, 1983
    Date of Patent: March 5, 1985
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Yoko Tanaka, Nobuo Ikekawa, Yoshiro Kobayashi
  • Patent number: 4500460
    Abstract: The invention provides a new derivative of vitamin D, 23,23-difluoro-25-hydroxycholecalciferol, a method for preparing said compound and various new intermediates utilized in such process.The compound is characterized by vitamin D-like activity as evidenced by its ability to increase intestinal calcium transport and serum calcium. It is further characterized by its resistance to hydroxylation at C-23, which is recognized as an essential metabolic step to the inactivation of vitamin D, and therefore should provide vitamin D-like activity of greater time duration.
    Type: Grant
    Filed: August 18, 1983
    Date of Patent: February 19, 1985
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Yoko Tanaka, Nobuo Ikekawa, Yoshiro Kobayashi
  • Patent number: 4411833
    Abstract: This invention provides a new method for preparing 26,26,26,27,27,27-hexafluoro-1,25-dihydroxycholesterol.The method permits the use of cholenic acid or an ester of cholenic acid as the starting material and the preparation of a compound which can be readily converted into a highly active derivative of vitamin D, 26,26,26,27,27,27-hexafluoro-1.alpha.,25-dihydroxycholecalciferol.
    Type: Grant
    Filed: May 26, 1982
    Date of Patent: October 25, 1983
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Yoko Tanaka, Nobuo Ikekawa, Yoshiro Kobayashi
  • Patent number: 4358406
    Abstract: This invention provides a new derivative of vitamin D, 26,26,26,27,27,27-hexafluoro-1.alpha.,25-dihydroxycholecalciferol, a process for preparing the same, and novel intermediate compounds.The compound is characterized by vitamin D-like activity substantially greater than that exhibited by 1.alpha.,25-dihydroxycholecalciferol which is considered to be the active hormonal form of vitamin D. The compound would find ready application as a substitute for vitamin D and in the treatment of or prophylaxis for disease states evincing metabolic calcium and phosphorous deficiences or imbalances.
    Type: Grant
    Filed: July 27, 1981
    Date of Patent: November 9, 1982
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Yoko Tanaka, Nobuo Ikekawa, Yoshiro Kobayashi
  • Patent number: 4307025
    Abstract: The invention provides new derivatives of vitamin D.sub.3, specifically, 1.alpha.,25-dihydroxy-2.beta.-fluorocholecalciferol.The compound is characterized by vitamin D-like activity as measured by its ability to stimulate intestinal calcium transport, mobilization of calcium from bone, increase serum inorganic phosphorous and in their antirachitic activity. The compound, could, therefore, find ready application as a substitute for vitamin D in its various known applications and in the treatment of various metabolic bone diseases.
    Type: Grant
    Filed: February 17, 1981
    Date of Patent: December 22, 1981
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Heinrich K. Schnoes, Nobuo Ikekawa, Yoko Tanaka, Masuo Morisaki, Jun-ichi Oshida
  • Patent number: 4305880
    Abstract: The invention provides a new derivative of vitamin D.sub.3, 24-fluoro-25-hydroxycholecalciferol.The compound is characterized by vitamin D-like activity in its ability to increase intestinal calcium transport, increase serum calcium and inorganic phosphorous concentration and to prevent the development of rickets. It would find ready application as a substitute for vitamin D.sub.3 and in the treatment of disease states evincing calcium-phosphorous imbalance and which are nonresponsive to vitamin D.sub.3 therapy.
    Type: Grant
    Filed: September 22, 1980
    Date of Patent: December 15, 1981
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Yoko Tanaka, Nobuo Ikekawa, Yoshiro Kobayashi
  • Patent number: 4254045
    Abstract: The invention provides new derivatives of vitamin D.sub.3, specifically, 1.alpha.-hydroxy-2.beta.-fluorocholecalciferol.The compound is characterized by vitamin D-like activity as measured by its ability to stimulate intestinal calcium transport, mobilize calcium from bone, increase serum inorganic phosphorous and in their antirachitic acitivity. The compound could, therefore, find ready application as a substitute for vitamin D in its various known applications and in the treatment of various metabolic bone diseases.
    Type: Grant
    Filed: April 21, 1980
    Date of Patent: March 3, 1981
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Nobuo Ikekawa, Yoko Tanaka, Masuo Morisaki, Jun-ichi Oshida
  • Patent number: 4248791
    Abstract: The invention provides a new derivative of vitamin D, 25-hydroxy-26,26,26,27,27,27-hexafluorocholecalciferol and a process for preparing the same.The compound is characterized by vitamin D-like activity in their ability to increase intestinal calcium transport, increase serum calcium and to prevent the development of rickets. These compounds would find ready application as a substitute for vitamin D and in the treatment of disease states evincing metabolic calcium and phosphorus deficiencies.
    Type: Grant
    Filed: February 4, 1980
    Date of Patent: February 3, 1981
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Yoko Tanaka, Nobuo Ikekawa, Yoshiro Kobayashi
  • Patent number: 4226788
    Abstract: The invention provides new derivatives of vitamin D, 24,24-difluoro-1.alpha.,25-dihydroxycholecalciferol and 24,24-difluoro-1.alpha.,25-dihydroxy-5,6-trans-cholecalciferol and processes for preparing the same.The compounds are characterized by vitamin D-like activity essentially equivalent to the vitamin D-like activity of 1.alpha.,25-dihydrocholecalciferol which is considered to be the hormonal form and most active derivative of vitamin D. The compounds of this invention are characterized by their ability to increase intestinal calcium transport, increase serum calcium and to prevent the development of rickets. These compounds would find ready application as a substitute for vitamin D and in the treatment of disease states evincing metabolic calcium and phosphorus deficiences.
    Type: Grant
    Filed: August 6, 1979
    Date of Patent: October 7, 1980
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Heinrich K. Schnoes, Nobuo Ikekawa, Yoko Tanaka, Yoshiro Kobayashi
  • Patent number: 4201881
    Abstract: The invention provides new derivatives of vitamin D, 24,24-difluoro-1.alpha.,25-dihydroxycholecalciferol and 24,24-difluoro-1.alpha.,25-dihydroxy-5,6-trans-cholecalciferol and processes for preparing the same.The compounds are characterized by vitamin D-like activity essentially equivalent to the vitamin D-like activity of 1.alpha.,25-dihydrocholecalciferol which is considered to be the hormonal form and most active derivative of vitamin D. The compounds of this invention are characterized by their ability to increase intestinal calcium transport, increase serum calcium and to prevent the development of rickets. These compounds would find ready application as a substitute for vitamin D and in the treatment of disease states evincing metabolic calcium and phosphorus deficiencies.
    Type: Grant
    Filed: March 28, 1979
    Date of Patent: May 6, 1980
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Heinrich K. Schnoes, Nobuo Ikekawa, Yoko Tanaka, Yoshiro Kobayashi
  • Patent number: 4196133
    Abstract: The invention provides a new derivative of vitamin D.sub.3, 24,24-difluoro-25-hydroxycholecalciferol.The compound is characterized by vitamin D-like activity in its ability to increase intestinal calcium transport, increase serum calcium and inorganic phosphorous concentration and to prevent the development of rickets. It would find ready application as a substitute for vitamin D.sub.3 and in the treatment of disease states evincing calcium-phosphorous imbalance and which are non-responsive to vitamin D.sub.3 therapy.
    Type: Grant
    Filed: March 5, 1979
    Date of Patent: April 1, 1980
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Hector F. DeLuca, Nobuo Ikekawa, Yoko Tanaka, Yoshiro Kobayashi
  • Patent number: 4022891
    Abstract: Novel 1.alpha., 24-dihydroxycholecalciferol and derivatives thereof which are useful with reduced side-effects for the treatment of abnormal metabolism of calcium and phosphorus caused by liver failure, renal failure, gastrointestinal tract failure and parathyroid failure, and related bone diseases. Preparation of the novel 1.alpha., 24-dihydroxycholecalciferol and their derivatives starts from 1.alpha., 24-dihydroxycholesterol prepared by reacting 1.alpha., 2.alpha.-epoxy-24-keto-cholesta-4,6-dien-3-one with an alkali metal and a proton donor in the presence of liquid ammonia or a liquid amine. Reaction of the 1.alpha., 24-dihydroxycholesterol with an allylic brominating agent, followed by contacting with a dehydrobrominating agent, affords 1.alpha.,3.beta., 24-trihydroxycholesta-5,7-diene derivative, which can then be converted to 1.alpha., 24-dihydroxycholocalciferol by ultraviolet irradiation in a organic solvent, followed by isomerization. Processes are also provided for separating 1.alpha.
    Type: Grant
    Filed: June 2, 1975
    Date of Patent: May 10, 1977
    Assignee: Teijin Limited
    Inventors: Toru Takeshita, Yoshinobu Hashimoto, Hiroyuki Kawashima, Sachio Ishimoto, Nobuo Ikekawa, Masuo Morisaki