Patents by Inventor Thomas A. Davidson

Thomas A. Davidson 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: 4766131
    Abstract: Analgesic 1,2,3,4-tetrahydroisoquinolines of the formula (1) ##STR1## wherein R.sub.1 and R.sub.2 respectively are hydrogen, hydroxy or alkoxy of 1 to 4 carbon atoms, R.sub.3 and R.sub.4 respectively are hydrogen or alkyl of 1 to 4 carbon atoms, and R.sub.5 is hydroxy, nitro or ##STR2## wherein R.sub.6 and R.sub.7 respectively are hydrogen, alkyl of 1 to 4 carbon atoms or RCO-- wherein R is hydrogen or alkyl of 1 to 4 carbon atoms; pharmaceutically acceptable addition salts thereof with non-toxic acids; analgesic compositions thereof in an inert, pharmaceutical carrier; and methods of preparation from corresponding R.sub.1, R.sub.2, R.sub.3 and R.sub.4 -substituted tetrahydroisoquinolines.
    Type: Grant
    Filed: December 30, 1986
    Date of Patent: August 23, 1988
    Assignee: Pennwalt Corporation
    Inventors: Thomas A. Davidson, Ronald C. Griffith
  • Patent number: 4603206
    Abstract: Novel 7-ether and 7-thioether derivatives of 2-aryl, 3-aryl, and 2,3-diaryl-2,5,6,7-tetrahydro-3H-pyrrolo[1,2-a]-imidazole and 8-ether and 8-thioether derivatives of 2-aryl, 3-aryl, and 2,3-diaryl-2,3,5,6,7,8-hexahydro-imidazo[1,2-a]-pyridine, such as 2,3,5,6,7,8-hexahydro-2-phenyl-8,8-dimethoxy-imidazo[1,2-a]pyridine hydrochloride, useful as immunomodulators. Diether derivatives are prepared by reacting the corresponding monothioether derivative with a positive halogenating agent in the presence of an alcohol.
    Type: Grant
    Filed: November 23, 1984
    Date of Patent: July 29, 1986
    Assignee: Pennwalt Corporation
    Inventors: Thomas A. Davidson, Robert J. Murray
  • Patent number: 4595759
    Abstract: The 2-aryl-1-aminoalkylcyclohexane nitrile, carboxylic acid or amide and derivatives thereof and methods of preparing same.
    Type: Grant
    Filed: February 15, 1985
    Date of Patent: June 17, 1986
    Assignee: Pennwalt Corporation
    Inventors: Thomas A. Davidson, Telfer L. Thomas
  • Patent number: 4560758
    Abstract: The instantly claimed invention is a process for preparing a 3-aryl or a 2,3-diaryl-2,5,6,7-tetrahydro-3H-pyrrole[1,2-a]imidazole or a 3-aryl or a 2,3-diaryl-2,3,5,6,7,8-hexa-hydroimidazo[1,2-a]pyridine which comprises (a) contacting the acid addition salt of the corresponding cyclic methylthioimine with a 2-aryl or a 2,3-diarylaziridine and (b) recovering from the resultant reaction mixture the desired compound, useful as immunomodulators.
    Type: Grant
    Filed: November 23, 1984
    Date of Patent: December 24, 1985
    Assignee: Pennwalt Corporation
    Inventors: Thomas A. Davidson, Robert J. Murray
  • Patent number: 4551535
    Abstract: The instantly claimed invention is a process for preparing novel 7-thioether derivatives of 2-aryl, 3 aryl, and 2,3-diary-2,5,7,7-tetra-hydro-3H-pyrrolo [1,2-a] imidazole and 8-thio-ether derivatives of 2-aryl, 3-aryl, and 2,3-diaryl-2,3,5,7,7,8-hexahydro-imidazo [1,2-a]-pyridine which comprises (a) contacting the corresponding amidine with about one molar equivalent of R.sub.1 SSR.sub.1 in the presence of about two molar equivalents of base and at a temperature of -78.degree. C. to about 0.degree. C. (b) contacting the corresponding amidine compound with about two molar equivalents of R,SSR, in the presence of about two molar equivalents of a base and at a temperature of from about -78.degree. C. to about 23.degree. C., said compounds being useful as immunomodulators.
    Type: Grant
    Filed: November 26, 1984
    Date of Patent: November 5, 1985
    Assignee: Pennwalt Corporation
    Inventors: Thomas A. Davidson, Robert J. Murray
  • Patent number: 4507481
    Abstract: Novel 7-ether and 7-thioether derivatives of 2-aryl, 3-aryl, and 2,3-diaryl-2,5,6,7-tetrahydro-3H-pyrrolo[1,2-a]-imidazole and 8-ether and 8-thioether derivatives of 2-aryl, 3-aryl, and 2,3-diaryl-2,3,5,6,7,8-hexahydro-imidazo[1,2-a]-pyridine, such as 2,3,5,6,7,8-hexahydro-2-phenyl-8,8-dimethoxy-imidazo[1,2-a]pyridine hydrochloride, useful as immunomodulators.
    Type: Grant
    Filed: July 29, 1983
    Date of Patent: March 26, 1985
    Assignee: Pennwalt Corporation
    Inventors: Thomas A. Davidson, Robert J. Murray
  • Patent number: 4282146
    Abstract: Certain 1,2,4,5-tetrahydro-7-alkoxy-(and 7,8-dialkoxy)-3H,3-benzazepines are prepared in excellent yields by a three step process comprising reacting a 3-alkoxy-(or 3,4-dialkoxy)-phenethylamine with a halo-acetaldehyde dialkylacetal to form the corresponding N-(2,2-dialkoxyethyl) phenethylamine, reacting that product with BF.sub.3 to close the ring and to form a 1-alkoxy-1,2,3,4-tetrahydro-7-alkoxy-(or 7,8-dialkoxy)-3H,3-benzazepine and reacting that product under reductive cleavage conditions to remove the 1-alkoxy group and to obtain the desired benzazepine. The benzazepines can be further reacted in the known manner or in the manner disclosed herein to form certain 3-substituted benzazepines.
    Type: Grant
    Filed: November 20, 1978
    Date of Patent: August 4, 1981
    Assignee: Pennwalt Corporation
    Inventors: Thomas A. Davidson, Ronald C. Griffith