Pharmaceutical compounds
CA 2014645 C · Owner: Tupper, David Edward · Inventors: Tupper, David Edward; Clark, Barry Peter
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides pharmaceutical compounds having the formula, in which R1 is hydrogen hydroxy, nitro, cyano, halo, amino, acetamido hydroxy-C1-4 alkyl, carboxaldehydo, C1-4 alkyl-carbonyl, carboxy, C1-4 alkoxy-carbonyl C1-4 alkyl, C1-4, alkoxy, C1-4 alkylthio C1-4 alkylsulphonyl or C1-4 alkoxy-C1-4 alkyl, R2 is hydrogen or halo, R3 is optionally substituted phenyl or optionally substituted phenyl ortho condensed with an optionally substituted ring selected from benzene cyclohexane, cyclohexene, cyclopentane or cyclopentene in which ring one of, the carbon atoms may be replaced by oxygen sulphur or nitrogen, and R4 is hydrogen C1-4 alkyl, C2-4 alkenyl or optionally …
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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 17, 1990 and granted May 30, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 17, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 17, 2012.
- 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.