Patents Assigned to Cocensys, Inc.
  • Patent number: 5319115
    Abstract: This invention provides a simplified method for converting pregnan-3,20-dione compounds to 3.alpha.-hydroxy,3.beta.-substituted-pregnanes. By selective use of reagents the unprotected dione is converted chemoselectively and diastereoselectively into a 3(R)-pregnan-3-spiro-2'oxirane-20-one intermediate. This intermediate can then be converted regioselectively by a second set of reactions to the 3.alpha.-hydroxy,3.beta.-substituted-20-one form, which can be further modified at the 20-keto position.Through this method, each ketone group is independently treated. By modifying the ketones one at a time, one can obtain the desired stereo-specificity at each site.
    Type: Grant
    Filed: March 4, 1992
    Date of Patent: June 7, 1994
    Assignee: Cocensys Inc.
    Inventors: Hasan Tahir, Michael Bolger, Richard Buswell, Richard Gabriel, Jay Stearns