Patents by Inventor Jong Kwon Choi

Jong Kwon Choi 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).

  • 1,3-diphenylpropane derivatives having inhibitory activity against tyrosinase and process for preparation thereof
    Patent number: 6093836
    Abstract: The present invention relates to a novel 1,3-diphenylpropane derivative having an inhibitory activity against tyrosinase represented by the following formula (I): ##STR1## in which - - represents double or single bond,R.sub.1 represents hydrogen or C.sub.1 -C.sub.10 alkyl,R.sub.2 represents C.sub.1 -C.sub.5 alkyl or C.sub.1 -C.sub.5 alkoxyalkyl, orR.sub.1 and R.sub.2 together represent a 5 to 6 membered heterocycle which can be substituted by C.sub.1 -C.sub.5 alkyl and which contains oxygen as the hetero atom,R.sub.3 represents hydrogen or C.sub.1 -C.sub.7 alkyl,R.sub.4 represents hydrogen, hydroxy, or oxo, andR.sub.5 and R.sub.6 mindependently of one another represent hydrogen or C.sub.1 -C.sub.5 alkyl.
    Type: Grant
    Filed: November 6, 1998
    Date of Patent: July 25, 2000
    Assignee: LG Chemical Ltd.
    Inventors: Young Ho Rhee, Kyung Ae Kim, Hyun Ho Lee, Jong Kwon Choi, Sang Hwa Lee