Patents by Inventor Calvin Vogel

Calvin Vogel 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).

  • Method of preparing etoposide
    Patent number: 5463040
    Abstract: The present invention relates to a method of increasing the yield of etoposide produced relative to prior art processes. A residue obtained as a result of reacting etoposide triacetate with a first lower alkanol in the presence of a first transesterification catalyst is provided. This residue is then reacted with a second lower alkanol and a second transesterification catalyst.
    Type: Grant
    Filed: June 28, 1994
    Date of Patent: October 31, 1995
    Assignee: Teva Pharmaceutical Industries, Ltd.
    Inventor: Calvin Vogel