The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 07, 1994
Filed:
Mar. 04, 1992
Hasan Tahir, Pasadena, CA (US);
Michael Bolger, Los Alamitos, CA (US);
Richard Buswell, Santa Rosa, CA (US);
Richard Gabriel, Woburn, MA (US);
Jay Stearns, Santa Rosa, CA (US);
Cocensys Inc., Irvine, CA (US);
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.