Patents by Inventor Henry G. Howell

Henry G. Howell 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).

  • Process for the preparation of nucleotides
    Patent number: 5591852
    Abstract: The present invention relates to a novel and economical process for the synthesis of HPMP-substituted nucleotide antiviral compounds. Also disclosed are novel intermediates produced in the process for the preparation of HPMPC.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 7, 1997
    Assignees: Institute of Organic Chemistry and Biochemistry of the Academy of Sciences of the Czech Republic, Rega Stichting v.z.w.
    Inventors: Purushotham Vemishetti, Paul R. Brodfuehrer, Henry G. Howell, Chester Sapino, Jr.
  • Process for the preparation of nucleotides
    Patent number: 5476938
    Abstract: The present invention relates to a novel and economical process for the synthesis of HPMP-substituted nucleotide antiviral compounds. Also disclosed are novel intermediates produced in the process for the preparation of HPMPC.
    Type: Grant
    Filed: January 21, 1992
    Date of Patent: December 19, 1995
    Assignees: Institute of Organic Chemistry and Biochemistry of the Academy of Sciences of the Czech Republic, Rega Stichting v.z.w.
    Inventors: Purushortham Vemishetti, Paul R. Brodfuehrer, Henry G. Howell, Chester Sapino, Jr.
  • Production of 2',3'-dideoxy-2',3'-didehydronucleosides
    Patent number: 5212294
    Abstract: There are disclosed novel processes for producing 2',3'-dideoxy-2'3'-didehydronucleosides, for example, 2',3'-dideoxy-2',3'-didehydrothymidine in high yields and on a large scale. The compounds so-produced are useful as antiviral agents, especially as agents effective against the human immunodeficiency viruses (HIV).
    Type: Grant
    Filed: March 31, 1992
    Date of Patent: May 18, 1993
    Assignee: Bristol-Myers Squibb Company
    Inventors: John E. Starrett, Jr., Muzammil M. Mansuri, John C. Martin, Carl E. Fuller, Henry G. Howell
  • Production of 2',3'-dideoxy-2',3'-didehydronucleosides
    Patent number: 5130421
    Abstract: There are disclosed novel processes for producing 2',3'-dideoxy-2'3'-didehydronucleosides, for example, 2',3'-dideoxy-2',3'-didehydrothymidine in high yields and on a large scale. The compounds so-produced are useful as antiviral agents, especially as agents effective against the human immunodeficiency viruses (HIV).
    Type: Grant
    Filed: April 29, 1991
    Date of Patent: July 14, 1992
    Assignee: Bristol-Myers Company
    Inventors: John E. Starrett, Jr., Muzammil M. Mansuri, John C. Martin, Carl E. Fuller, Henry G. Howell
  • Production of 2',3'-dideoxy-2',3'-didehydronucleosides
    Patent number: 4904770
    Abstract: There are disclosed novel processes for producing 2',3'-dideoxy-2'3'-didehydronucleosides, for example, 2',3'-dideoxy-2',3'-didehydrothymidine in high yields and on a large scale. The compounds so-produced are useful as antiviral agents, especially as agents effective against the human immunodeficiency viruses (HIV).
    Type: Grant
    Filed: March 24, 1988
    Date of Patent: February 27, 1990
    Assignee: Bristol-Myers Company
    Inventors: John E. Starrett, Jr., Muzammil M. Mansuri, John C. Martin, Carl E. Fuller, Henry G. Howell
  • Nucleoside process
    Patent number: 4879377
    Abstract: Process for producing 1-halo-2-deoxy-2-fluoroarabinofuranoside derivatives bearing protective ester groups from 1,3,5-tri-O-acylribofuranose; the 1-halo compounds are intermediates in the synthesis of therapeutically active nucleosidic compounds.
    Type: Grant
    Filed: July 28, 1988
    Date of Patent: November 7, 1989
    Assignee: Bristol-Myers Company
    Inventors: Steven P. Brundidge, Henry G. Howell, Chester Sapino, Jr., Chou Hong-Tann
  • Nucleoside process
    Patent number: 4625020
    Abstract: Process for producing 1-halo-2-deoxy-2-fluoroarabinofuranoside derivatives bearing protective ester groups from 1,3,5-tri-O-acylribofuranose; the 1-halo compounds are intermediates in the synthesis of therapeutically active nucleosidic compounds.
    Type: Grant
    Filed: November 18, 1983
    Date of Patent: November 25, 1986
    Assignee: Bristol-Myers Company
    Inventors: Steven P. Brundidge, Henry G. Howell, Chester Sapino, Jr., Chon-Hong Tann
  • Hydrogenation process
    Patent number: 4125724
    Abstract: An improved and novel process is provided for the reduction of isocyanate groups in organic compounds to formamide groups by catalytic hydrogenation with a noble metal catalyst. The process allows preparation of formamides in consistently high yields from all types of isocyanates.
    Type: Grant
    Filed: October 6, 1977
    Date of Patent: November 14, 1978
    Assignee: Bristol-Myers Company
    Inventor: Henry G. Howell
  • 2-Amino-1-(2,5-dimethoxyphenyl)-butanes
    Patent number: 4105695
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1 is Cl, Br, (lower)alkylthio or ##STR2## in which R.sup.3 is H or (lower)alkyl including the racemic mixtures and the dextrorotatory and levorotatory isomers, and the pharmaceutically acceptable non-toxic salts thereof have been found to enhance the learning capacity of mammals, including man, and to improve the mental alertness and attitudes of geriatrics without producing the undesirable stimulant side effects associated with the use of amphetamines.
    Type: Grant
    Filed: May 11, 1977
    Date of Patent: August 8, 1978
    Assignee: Bristol-Myers Company
    Inventors: Richard A. Partyka, Robert T. Standridge, Henry G. Howell, Alexander T. Shulgin