Process for the preparation of 10-(2-propynyl)estr-4-ene-3,17-dione
CA 2043280 A1 · Owner: Merrell Dow Pharmaceuticals (Canada) Inc. · Inventors: Benson, Harvey D.; Whitten, Jeffrey P.; Rand, Cynthia L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a process for the preparation of 10-(2-propynyl)-estr-4-ene-3,17-dione whereby this, compound is synthesized utilizing ketals prepared from the addition of 2,2-dimethyl-1,3-propanediol to the starting compound, 19-norandrost-5(10)-ene-3,17-dione (NAD). A new process for the addition of the propynyl group to steroid epoxides by means of higher order cuprates is also described herein. M01373A
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed May 24, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 24, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 24, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.