Patents by Inventor Haijun Nan

Haijun Nan 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 preparing quinolonecarboxylic acids
    Patent number: 6699992
    Abstract: The present invention provides a process for preparing quinolonecarboxylic acid derivatives having the formula (I): wherein R1 is H, halogen, or amino; R2 is halogen; R3 is H, halogen, C1-4 alkoxyl, or CN; R4 is selected from the group consisting of C3-6cycloalkyl, C1-4alkyl, C1-4alkoxyC1-4alkyl, and C1-4alkylaminoC1-4alkyl. The invention also provides new acetophenones having the formula (II) that are intermediates for preparing the compound of the formula (I).
    Type: Grant
    Filed: February 12, 2003
    Date of Patent: March 2, 2004
    Assignee: Lynchem Co., Ltd.
    Inventors: Yuncai Wang, Rongye Chen, Haijun Nan
  • Process for preparing a quinolone-carboxylic acid
    Publication number: 20030166936
    Abstract: The present invention provides a process for preparing quinolonecarboxylic acid derivatives having the formula (I): 1
    Type: Application
    Filed: February 12, 2003
    Publication date: September 4, 2003
    Inventors: Yuncai Wang, Rongye Chen, Haijun Nan