Patents by Inventor Vinayakam Subramanyam

Vinayakam Subramanyam 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: 5637748
    Abstract: Syntheses of fluorinated amide and fluorinated nitrile compounds are improved by use of particular media for the reactions. Fluorinated amide can also be synthesized in high yield in a neat reaction.
    Type: Grant
    Filed: March 1, 1995
    Date of Patent: June 10, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ming-Hong Hung, Vinayakam Subramanyam
  • Patent number: 5324824
    Abstract: A method for preparing a coordination complex of an isonitrile ligand and a radioisotope of Tc, Ru, Co, Pt, Re, Os, Ir, W, Re, Cr, Mo, Mn, Ni, Rh, Nb and Ta from a non-radioactive metal adduct of the isonitrite.
    Type: Grant
    Filed: March 12, 1991
    Date of Patent: June 28, 1994
    Assignee: The DuPont Merck Pharmaceutical Co.
    Inventors: Alan B. Carpenter, Jr., Leo J. Maheu, Michael A. Patz, Thomas H. Tulip, Karen E. Linder, Vinayakam Subramanyam, Jeffery S. Thompson
  • Patent number: 5069828
    Abstract: An improved process for preparing benzenesulfonate salts, such as 4-nonanoyloxybenzenesulfonic acid, sodium salt, from an appropriately substituted acid chloride or chloroformate and a hydroxybenzenesulfonic acid in which the reaction is conducted in the presence of a phase transfer catalyst selected from quaternary ammonium and quaternary phosphonium salts.
    Type: Grant
    Filed: June 6, 1989
    Date of Patent: December 3, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Donald J. Dumas, Vinayakam Subramanyam
  • Patent number: 4988827
    Abstract: Ether-substituted isonitriles, Tc99m complexes thereof, and processes for myocardial tissue radioimaging using the Tc99m complexes.
    Type: Grant
    Filed: June 1, 1987
    Date of Patent: January 29, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Paul L. Bergstein, Vinayakam Subramanyam
  • Patent number: 4985180
    Abstract: Phenyl esters of substituted acids are prepared by a two-step process in which a phenol derivative is first treated with an acid halide to yield a phenyl ester intermediate, and the intermediate is reacted with an appropriate nucleophile.
    Type: Grant
    Filed: June 6, 1989
    Date of Patent: January 15, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Harold E. Bellis, Donald J. Dumas, George C. Sonnichsen, Vinayakam Subramanyam
  • Patent number: 4894445
    Abstract: A method for preparing a coordination complex of an isonitrile ligand and a radioisotope of Tc, Ru, Co, Pt, Re, Os, Ir, W, Re, Cr, Mo, Mn, Ni, Rh, Nb and Ta from a non-radioactive metal adduct of the isonitrile.
    Type: Grant
    Filed: June 25, 1986
    Date of Patent: January 16, 1990
    Assignee: E. I. Du Pont De Nemours and Company
    Inventors: Alan P. Carpenter, Jr., Leo J. Maheu, Michael A. Patz, Thomas H. Tulip, Karen E. Linder, Vinayakam Subramanyam, Jeffery S. Thompson
  • Patent number: 4526776
    Abstract: An hepatobiliary imaging agent is disclosed which is a cationic complex of Tc-99m, a cyanate or thiocyanate ion, and a mono or polydentate organic ligand having one or more donor atoms, each with a free-electron pair available for accepting a proton or for complexing with Tc-99m to form a cationic complex. These complexes can provide images of the hepatobiliary transit in as little as ten minutes.
    Type: Grant
    Filed: April 15, 1983
    Date of Patent: July 2, 1985
    Assignee: E. I. du Pont de Nemours & Company
    Inventors: Vinayakam Subramanyam, Algis Rajeckas
  • Patent number: 4451450
    Abstract: A normally solid, hydrophilic compound capable of binding with Tc-99m to form a cationic complex is provided. The compound has a formula selected from: ##STR1## wherein: R, R', R", R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are each independently selected from hydrogen; or substituted or unsubstituted alkyl, alkylene, aryl, alkylaryl, arylalkyl, monocycloalkyl, polycycloalkyl, heterocyclic and carbocyclic groups; and R plus R.sup.i in formula (A) may be taken together to form a cyclic compound;A, A', A", A.sup.1, A.sup.2, A.sup.3, A.sup.4, A.sup.5 and A.sup.6 are independently neutral functional elements, each having a free electron pair available for accepting a proton to provide a charged ligand and having the capability of complexing with Tc-99m to form a cationic complex;Y.sup.1, Y.sup.2, Y.sup.3, Y.sup.4, Y.sup.5 and Y.sup.
    Type: Grant
    Filed: October 15, 1981
    Date of Patent: May 29, 1984
    Assignee: New England Nuclear Corporation
    Inventor: Vinayakam Subramanyam