Process for the production of unsaturated 17.alpha.-cyanomethyl -17.beta. hydroxy steroids
CA 2086919 C · Owner: Jenapharm Gmbh · Inventors: Muller, Gerd; Teichmuller, Gerhard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to an unsaturated 15-dehydro-17.alpha.-cyanomethyl-17.beta.-hydroxy steroid of the formula I (I), wherein R1 is methyl or ethyl; R2 is selected from the group consisting of hydrogen and methyl; R3 is selected from the group consisting of hydrogen, hydroxy, acetoxy and alkoxy having 1 to 6 carbon atoms; R4 is hydrogen and R5 is selected from the group consisting of hydroxy, acetoxy and alkoxy having 1 to 6 carbon atoms, or R4 and R5 are both methoxy or both ethoxy or, R4 and R5, together, represent a keto group or a ketal group selected from the group consisting of -O-CH2-CH2-O-; -O-CH2-C(CH3)2-CH2-O- and -OCH(CH3)-CH2-CH(CH3)-O-; wherein said steroids of formula (I) …
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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 July 5, 1991 and granted February 24, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 5, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 5, 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.