Process for the production of 4-pregnene-3,20-dione and its derivatives
CA 2070391 C · Owner: Kennecke, Mario · Inventors: Kennecke, Mario; Weber, Alfred
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the production of 4-pregnene-3,20-dione and its derivatives of general formula I, in which R1 means a hydrogen atom, a fluorine atom or a methyl group R2 represents a hydrogen atom or a hydroxy group and, R3 and R4 together symbolize a carbon-carbon bond or R3 represents a hydrogen atom, a hydroxy group or an alkanoyloxy group with up to 6 carbon atoms and R4 means a hydrogen atom or a methyl group is described, which is characterized in that a pregnane derivative of general formula II in which R1, R3 and R4 have the above-mentioned meaning ~ symbolizes a single bond or a double bond R5 represents a hydrogen atom, a hydroxy group or an alkanoyloxy group with at most 6 carbon …
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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 30, 1991 and granted May 1, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 30, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 30, 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.