Patents by Inventor Abram K. Sheynkman

Abram K. Sheynkman 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 for the preparation of (+)-calanolide A and intermediates thereof
    Patent number: 5489697
    Abstract: A method for preparing (.+-.)-calanolide A, 1, a potent HIV reverse transcriptase inhibitor, from chromene 4 is provided. Useful intermediates for preparing (.+-.)-calanolide A and its derivatives are also provided.According to the disclosed method, chromene 4 intermediate was reacted with acetaldehyde diethyl acetal in the presence of an acid catalyst with heating to produce chromanone 7. Reduction of chromene 7 with sodium borohydride, in the presence of cerium trichloride, produced (.+-.)-calanolide A, which was purified chromatographically.
    Type: Grant
    Filed: August 3, 1994
    Date of Patent: February 6, 1996
    Assignee: MediChem Research, Inc.
    Inventors: William A. Boulanger, Michael T. Flavin, Alla Kucherenko, Abram K. Sheynkman