Patents by Inventor Hans Panskus

Hans Panskus 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 fluoroquinolonecarboxylic acids
    Patent number: 6590101
    Abstract: Fluoroquinolonecarboxylic acids can be prepared by hydrolysis of the corresponding C1-C4-alkyl esters with addition of water, acetic acid, and sulfuric acid using a drastically reduced amount of sulfuric acid if, relative to 1 mol of C1-C4-alkyl fluoroquinolonecarboxylate, less than 30 g of sulfuric acid are employed, the reaction mixture is heated to reflux for 0.5 to 8 hours, then a mixture of acetic acid, C1-C4-alkyl acetate, C1-C4-alkyl alcohol, and optionally water is distilled off, and finally the fluoroquinolonecarboxylic acid prepared is isolated.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: July 8, 2003
    Assignee: Bayer Aktiengesellschaft
    Inventors: Norbert Lui, Hans Panskus
  • Process for the preparation of fluoroquinolonecarboxylic acids
    Publication number: 20020120138
    Abstract: Fluoroquinolonecarboxylic acids can be prepared by hydrolysis of the corresponding C1-C4-alkyl esters with addition of water, acetic acid, and sulfuric acid using a drastically reduced amount of sulfuric acid if, relative to 1 mol of C1-C4-alkyl fluoroquinolonecarboxylate, less than 30 g of sulfuric acid are employed, the reaction mixture is heated to reflux for 0.5 to 8 hours, then a mixture of acetic acid, C1-C4-alkyl acetate, C1-C4-alkyl alcohol, and optionally water is distilled off, and finally the fluoroquinolonecarboxylic acid prepared is isolated.
    Type: Application
    Filed: February 19, 2002
    Publication date: August 29, 2002
    Inventors: Norbert Lui, Hans Panskus
  • Process for preparing substituted pyridines
    Patent number: 6392050
    Abstract: The invention relates to a process for preparing substituted pyridines in a simple and cost-effective manner in good yields by reacting substituted 1,4-dihydropyridines with methyl nitrite in the presence of an acid that contains less than 20% by weight of oxidizing components.
    Type: Grant
    Filed: June 4, 2001
    Date of Patent: May 21, 2002
    Assignee: Bayer Aktiengesellschaft
    Inventors: Norbert Lui, Hans Panskus, Albert Schnatterer
  • Process for preparing substituted pyridines
    Publication number: 20020002285
    Abstract: The invention relates to a process for preparing substituted pyridines in a simple and cost-effective manner in good yields by reacting substituted 1,4-dihydropyridines with methyl nitrite in the presence of an acid that contains less than 20% by weight of oxidizing components.
    Type: Application
    Filed: June 4, 2001
    Publication date: January 3, 2002
    Inventors: Norbert Lui, Hans Panskus, Albert Schnatterer
  • Process for preparing quinolone- and naphthyridone- carboxylic acids and esters thereof
    Patent number: 6229017
    Abstract: An improved process for preparing quinolone- and naphthyridonecarboxylic acids and esters thereof from benzoyl chlorides and nicotinoyl chlorides, respectively, in which the reaction carried out in the presence of a non-polar to slightly polar solvent without separation of intermediaries that form during the process.
    Type: Grant
    Filed: June 11, 1999
    Date of Patent: May 8, 2001
    Assignee: Bayer Aktiengesellschaft
    Inventors: Norbert Lui, Hans Panskus, Herbert Müller