Tertiary alkyl functionalized piperazine derivatives
CA 2015033 C · Owner: John Wyeth & Brother Limited · Inventors: Abou-Gharbia, Magid A.; Cliffe, Ian A.; Yardley, John P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Compounds of the formula:, (see formula I) in which R1 is alkyl; R2 and R3 are alkyl or taken together they are polymethylene, R2 and R3 complete a 5-norbornen-2-yl moiety; X is -CO2- -OCO-, -OCO2, - N(R7)CO-, -NHNHCO-, -ON(R7)CO- -CON(R7)-, -N(R7)CO2-, -OCON(R7)-, or -N(R7)CON(R8)wherein R7 and R8 are, independently, hydrogen alkyl, phenyl, benzyl, substituted phenyl or substituted, benzyl in which the substituents are halo alkyl, alkoxy, cyano, nitro or, perhalomethyl; R4 is hydrogen or alkyl; R5 is hydrogen alkyl, hydroxyalkyl, phenyl, benzyl, substituted phenyl or substituted benzyl in which the substituents, are hydroxy, halo, alkyl alkoxy, trifluoromethyl, nitro, cyano, carbalkoxy …
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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 April 20, 1990 and granted June 6, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 20, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 20, 2012.
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Timeline
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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.