Patents by Inventor Axel Nurrenbach

Axel Nurrenbach 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).

  • Preparation of N-(D)-ribityl-2-phenylazo-4,5-dimethylaniline
    Patent number: 4360669
    Abstract: A process for the preparation of N-(D)-ribityl-2-phenylazo-4,5-dimethylaniline (I), wherein1. in the case of pure or virtually pure (D)-ribose (III)(a) the latter is reacted with 3,4-dimethylnitrobenzene (IVa) or 3,4-dimethylaniline (IVb) and with hydrogen in the presence of a hydrogenation catalyst,(b) the resulting solution is reacted, in a conventional manner, with an acid phenyldiazonium salt solution (VI) and(c) the resulting product is isolated by crystallization, in a conventional manner, or2. in the case of crude ribose, ie.
    Type: Grant
    Filed: July 24, 1981
    Date of Patent: November 23, 1982
    Assignee: BASF Aktiengesellschaft
    Inventors: Wolfram Schmidt, Joachim Paust, Axel Nurrenbach