Patents by Inventor David L. Kuo

David L. Kuo 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).

  • Publication number: 20120226044
    Abstract: A process for the preparation of 4-steroids of the formula: R1 and R2 are independently selected from the group that is hydrogen, F, Cl, Br, I, C1-6-allyl and C1-6-alkoxy, and R4 is selected from the group that is hydrogen, (N,N-di-C1-6-allylamino)methyl, allylamino)ethyl, C1-6-alkyl, C1-6-alkoxy, phenyl and benzyl, and Q7 represents a carbonyl oxygen atom or is R7-1 and R7-2, wherein one of R7-1 and R7-2 is hydrogen and the other is selected from the group that is hydrogen, F, Cl, Br, I, C1-6-alkyl and C1-6-alkoxy, and R9 represents hydrogen or F, and Q11 represents a carbonyl oxygen atom or is R11-1 and R11-2, wherein one of R11-1 and R11-2 is hydrogen and the other is selected from the group that is hydrogen, cyano, cyano-C1-3-alkyl, acetoxy, COOH and COO?M+, wherein M+ is Na+, K+ or NH+4, and R16 is selected from the group that is hydrogen, cyano, cyano-C1-3-alkyl, acetoxy, COOH and COO?M+, wherein M+ is Na+, K+ or NH+4, and COOR represents COOH or COO?M+, wherein M+ is Na+, K+ or NH+4.
    Type: Application
    Filed: July 4, 2005
    Publication date: September 6, 2012
    Inventors: Yves Bessard, David L. Kuo
  • Patent number: 5919992
    Abstract: The present invention relates to process of halogenating an alkynol having 3 to 20 carbon atoms to produce a compound having the formula: R-C.tbd.(C--CH.sub.2).sbsb.x-OH, wherein R is F, Cl, Br or I and x is 1 to 18. In particular, this invention provides a process for preparing a halopropynyl alcohol, specifically iodopropynyl alcohol. In one embodiment, iodopropynyl alcohol is produced by sequentially adding potassium hydroxide, potassium iodide and an oxidizing agent to a solution of propynyl alcohol at a rate and temperature sufficient to produce an iodopropynyl alcohol.
    Type: Grant
    Filed: June 11, 1996
    Date of Patent: July 6, 1999
    Assignee: Lonza, Inc.
    Inventor: David L. Kuo
  • Patent number: 5498715
    Abstract: A process for preparing imidazopyridine derivatives of the general formula: ##STR1## wherein R.sub.1 is hydrogen or an alkyl group, and R.sub.2, R.sub.3 and R.sub.4 are identical or different and are hydrogen, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or a halogen atom. In this process, a 2-amino-3-nitropyridine is hydrogenated in the presence of a hydrogenation catalyst and the hydrogenation product is condensed with a carboxylic acid simultaneously present in the reaction mixture to give the end product. The imidazopyridine derivatives are intermediates for the preparation of angiotensin II antagonists.
    Type: Grant
    Filed: November 29, 1994
    Date of Patent: March 12, 1996
    Assignee: Lonza Ltd.
    Inventors: David L. Kuo, Martin Eyer, Jean-Paul Roduit, Alain Wellig
  • Patent number: 5221748
    Abstract: Process for the production of 2,3-dichloro-5-acetylpyridine by reaction of a 5,6-dichloronicotinic acid halide with a methyl magnesium halide in an inert organic diluent. The reaction is performed in the presence of a Cu/Cu halide as the catalyst.
    Type: Grant
    Filed: March 12, 1991
    Date of Patent: June 22, 1993
    Assignee: Lonza Ltd.
    Inventor: David L. Kuo
  • Patent number: 5204465
    Abstract: A process for the production of piperazinylpyrimidine derivatives of the formula: ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are the same or different and each is a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, branched or unbranched. These piperazinylpyrimidine derivatives are acid-converted with cyanamide to an amidine salt starting from piperazine or its hydrate and then reacted with a dicarbonyl compound in the presence of a base to the end product.
    Type: Grant
    Filed: December 6, 1991
    Date of Patent: April 20, 1993
    Assignee: Lonza Ltd.
    Inventors: David L. Kuo, Robert Voeffray
  • Patent number: 5200520
    Abstract: A process for the production of piperazinylpyrimidine derivatives of the formula I: ##STR1## wherein R.sub.1 is a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, branched or unbranched. In the process, piperazine or its hydrate is acid-converted with cyanamide to an amidine salt and the latter is then reacted with a carbonyl compound in the presence of a base to the end product.
    Type: Grant
    Filed: December 10, 1991
    Date of Patent: April 6, 1993
    Assignee: Lonza Ltd.
    Inventor: David L. Kuo