Patents by Inventor Donald E. Kuhla

Donald E. Kuhla 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: 4435584
    Abstract: 2-Methyl-3-hydroxy-4H-pyran-4-one is prepared by contacting 1(2-furyl)-1-ethanol in aqueous solution with two equivalents of a halogen oxidant at room temperature and then heating until the hydrolysis of the formed 4-halo-dihydropyran intermediate is substantially complete. Other valuable related gamma-pyrones are prepared in analogous manner from appropriate alcohols.
    Type: Grant
    Filed: July 19, 1982
    Date of Patent: March 6, 1984
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4387235
    Abstract: 2-methyl-3-hydroxy-4H-pyran-4-one is prepared by contacting 1(2-furyl)-1-ethanol in aqueous solution with two equivalents of a halogen oxidant at room temperature and then heating until the hydrolysis of the formed 4-halo-dihydropyran intermediate is substantially complete. Other valuable related gammapyrones are prepared in analogous manner from appropriate alcohols.
    Type: Grant
    Filed: October 14, 1981
    Date of Patent: June 7, 1983
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4368331
    Abstract: (2-methyl-3-hydroxy-4h-pyran-4-one is prepared by contacting 1(2-furyl)-1-ethanol in aqueous solution with two equivalents of a halogen oxidant at room temperature and then heating until the hydrolysis of the formed 4-halo-dihydro-pyran intermediate is substantially complete. Other valuable related gamma-pyrones are prepared in analogous manner from appropriate alcohols.
    Type: Grant
    Filed: November 13, 1979
    Date of Patent: January 11, 1983
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Donald E. Kuhla, Paul D. Weeks
  • Patent number: 4323506
    Abstract: 2-Methyl-3-hydroxy-4H-pyran-4-one is prepared by contacting 1(2-furyl)-1-ethanol in aqueous solution with two equivalents of a halogen oxidant at room temperature and then heating until the hydrolysis of the formed 4-halo-dihydropyran intermediate is substantially complete. Other valuable related gammapyrones are prepared in analogous manner from appropriate alcohols.
    Type: Grant
    Filed: September 4, 1979
    Date of Patent: April 6, 1982
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4289704
    Abstract: 2-Methyl-3-hydroxy-4H-pyran-4-one is prepared by contacting 1(2-furyl)-1-ethanol in aqueous solution with two equivalents of a halogen oxidant at room temperature and then heating until the hydrolysis of the formed 4-halo-dihydropyran intermediate is substantially complete. Other valuable related gamma-pyrones are prepared in analogous manner from appropriate alcohols.
    Type: Grant
    Filed: July 2, 1980
    Date of Patent: September 15, 1981
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4219483
    Abstract: Novel 2,3,6-substituted-4-pyrones having activity as prostaglandin antagonists are disclosed, together with intermediates useful for the preparation thereof. Methods of using the compounds of this invention as prostaglandin antagonists are described.
    Type: Grant
    Filed: September 11, 1978
    Date of Patent: August 26, 1980
    Assignee: Pfizer Inc.
    Inventors: Donald E. Kuhla, Jacob J. Plattner
  • Patent number: 4191693
    Abstract: Gamma-pyrones are prepared by contacting a 3-halo-furfuryl alcohol or a 3-alkoxy-furfuryl alcohol with one equivalent of a halogen, peracid or peroxide oxidant and then heating until hydrolysis of the formed 4-substituted-dihydropyran intermediate is substantially complete. Maltol (2-methyl-3-hydroxy-4H-pyran-4-one) is prepared by this process from 2(1-hydroxyethyl)-3-alkoxy furans or 2(1-hydroxyethyl)-3-halo-furans. Gamma-pyrones are also prepared by contacting the corresponding 3-substituted-2,5-dialkoxy-furfuryl alcohols with acid until conversion to the gamma-pyrones is substantially complete.
    Type: Grant
    Filed: August 28, 1978
    Date of Patent: March 4, 1980
    Assignee: Pfizer, Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4173572
    Abstract: Gamma-pyrones are prepared by contacting a 3-halo-furfuryl alcohol or a 3-alkoxy-furfuryl alcohol with one equivalent of a halogen, peracid or peroxide oxidant and then heating until hydrolysis of the formed 4-substituted-dihydropyran intermediate is substantially complete. Maltol (2-methyl-3-hydroxy-4H-pyran-4-one) is prepared by this process from 2(1-hydroxyethyl)-3-alkoxy furans or 2(1-hydroxyethyl)-3-halo-furans. Gamma-pyrones are also prepared by contacting the corresponding 3-substituted-2,5-dialkoxy-furfuryl alcohols with acid until conversion to the gamma-pyrones is substantially complete.
    Type: Grant
    Filed: August 28, 1978
    Date of Patent: November 6, 1979
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4163745
    Abstract: The synthesis of imidazo[1,2-a]pyridinium, imidazo[1,5-a]pyridinium, pyrrolo[1,2-a]pyrazinium, pyrazolo[1,5-a]pyridinium, imidazo[2,1-a]isoquinolinium and imidazo[5,1-a]isoquinolinium quaternary salts and their use as hypoglycemic agents.
    Type: Grant
    Filed: August 8, 1977
    Date of Patent: August 7, 1979
    Assignee: Pfizer Inc.
    Inventor: Donald E. Kuhla
  • Patent number: 4147705
    Abstract: 2-Methyl-3-hydroxy-4H-pyran-4-one is prepared by contacting 1(2-furyl)-1-ethanol in aqueous solution with two equivalents of a halogen oxidant at room temperature and then heating until the hydrolysis of the formed 4-halo-dihydropyran intermediate is substantially complete. Other valuable related gamma-pyrones are prepared in analogous manner from appropriate alcohols.
    Type: Grant
    Filed: January 16, 1978
    Date of Patent: April 3, 1979
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4141898
    Abstract: The synthesis of imidazo[1,2-a]pyridinium, imidazo[1,5-a]pyridinium, pyrrolo[1,2-a]pyrazinium, pyrazolo[1,5-a]pyridinium, imidazo[2,1-a]isoquinolinium and imidazo[5,1-a]isoquinolinium quaternary salts and their use as hypoglycemic agents.
    Type: Grant
    Filed: August 8, 1977
    Date of Patent: February 27, 1979
    Assignee: Pfizer Inc.
    Inventor: Donald E. Kuhla
  • Patent number: 4136096
    Abstract: 6-Amino and 6-(N-protected amino)-2,2-dimethyl-3-cyanopenams, intermediates therefor, and a process for the conversion of the 3-cyano penams, by reaction with a source of azide ion in a reaction inert solvent, to 6-amino-and 6-(N-protected amino)-2,2-dimethyl-3(5-tetrazolyl)penams, intermediates for the preparation of antibacterial agents.
    Type: Grant
    Filed: November 18, 1977
    Date of Patent: January 23, 1979
    Assignee: Pfizer Inc.
    Inventor: Donald E. Kuhla
  • Patent number: 4132847
    Abstract: Novel 2,3,6-substituted-4-pyrones having activity as prostaglandin antagonists are disclosed, together with intermediates useful for the preparation thereof. Methods of using the compounds of this invention as prostaglandin antagonists are described.
    Type: Grant
    Filed: July 22, 1977
    Date of Patent: January 2, 1979
    Assignee: Pfizer Inc.
    Inventors: Donald E. Kuhla, Jacob J. Plattner
  • Patent number: 4129567
    Abstract: The synthesis of imidazo[1,2-a]pyridinium, imidazo[1,5-a]pyridinium, pyrrolo[1,2-a]pyrazinium, pyrazolo[1,5-a]pyridinium, imidazo[2,1-a]isoquinolinium and imidazo[5,1-a]isoquinolinium quaternary salts and their use as hypoglycemic agents.
    Type: Grant
    Filed: August 8, 1977
    Date of Patent: December 12, 1978
    Assignee: Pfizer Inc.
    Inventor: Donald E. Kuhla
  • Patent number: 4126624
    Abstract: Gamma-pyrones are prepared by contacting a 3-halo-furfuryl alcohol or a 3-alkoxy-furfuryl alcohol with one equivalent of a halogen, peracid or peroxide oxidant and then heating until hydrolysis of the formed 4-substituted-dihydropyran intermediate is substantially complete. Maltol (2-methyl-3-hydroxy-4H-pyran-4-one) is prepared by this process from 2(1-hydroxyethyl)-3-alkoxy furans or 2(1-hydroxyethyl)-3-halo-furans. Gamma-pyrones are also prepared by contacting the corresponding 3-substituted-2,5-dialkoxy-furfuryl alcohols with acid until conversion to the gamma-pyrones is substantially complete.
    Type: Grant
    Filed: November 12, 1976
    Date of Patent: November 21, 1978
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4107430
    Abstract: Trans-N,N-dimethyl-9-[3-(4-methyl-1-piperazinyl)propylidene]-thioxanthene-2 -sulfonamide is isomerized to the cis-isomer by contacting the trans-isomer with strong base in a polar organic solvent. By using an organic solvent in which the solubility of the cis-isomer is substantially less than that of the trans-isomer, the cis-isomer can be selectively precipitated from said solvent, thereby favoring additional isomerization to the cis-isomer in the supernatant, and separated.
    Type: Grant
    Filed: October 20, 1976
    Date of Patent: August 15, 1978
    Assignee: Pfizer Inc.
    Inventors: Donald E. Kuhla, Harry A. Watson, Jr.
  • Patent number: 4097598
    Abstract: The synthesis of imidazo?1,2-a!pyridinium, imidazo?1,5-a!pyridinium, pyrrolo?1,2-a!pyrazinium, pyrazolo?1,5-a!pyridinium, imidazo?2,1-a!isoquinolinium and imidazo?5,1-a!isoquinolinium quaternary salts and their use as hypoglycemic agents.
    Type: Grant
    Filed: August 8, 1977
    Date of Patent: June 27, 1978
    Assignee: Pfizer Inc.
    Inventor: Donald E. Kuhla
  • Patent number: 4093616
    Abstract: The synthesis of imidazo[1,2-a]pyridinium, imidazo[1,5-a]pyridinium, pyrrolo[1,2-a]pyrazinium, pyrazolo[1,5-a]pyridinium, imidazo[2,1-a]isoquinolinium and imidazo[5,1-a]isoquinolinium quaternary salts and their use as hypoglycemic agents.
    Type: Grant
    Filed: August 8, 1977
    Date of Patent: June 6, 1978
    Assignee: Pfizer Inc.
    Inventor: Donald E. Kuhla
  • Patent number: 4082717
    Abstract: 2-METHYL-3-HYDROXY-4H-pyran-4-one is prepared by contacting 1(2-furyl)-1-ethanol in aqueous solution with two equivalents of a halogen oxidant at room temperature and then heating until the hydrolysis of the formed 4-halo-dihydropyran intermediate is substantially complete. Other valuable related gamma-pyrones are prepared in analogous manner from appropriate alcohols.
    Type: Grant
    Filed: September 9, 1976
    Date of Patent: April 4, 1978
    Assignee: Pfizer Inc.
    Inventors: Thomas M. Brennan, Daniel P. Brannegan, Paul D. Weeks, Donald E. Kuhla
  • Patent number: 4081455
    Abstract: 6-AMINO AND 6-(N-protected amino)-2,2-dimethyl-3-cyanopenams, intermediates therefor, and a process for the conversion of the 3-cyano penams, by reaction with a source of azide ion in a reaction inert solvent, to 6-amino-and 6-(N-protected amino)-2,2-dimethyl-3(5-tetrazolyl)penams, intermediates for the preparation of antibacterial agents.
    Type: Grant
    Filed: February 25, 1977
    Date of Patent: March 28, 1978
    Assignee: Pfizer Inc.
    Inventor: Donald E. Kuhla