Heterocyclic compounds
CA 2050197 A1 · Owner: Winternitz, Paul · Inventors: Winternitz, Paul; Wenger, Jean; Zeller, Martin
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Heterocyclic compounds Abstract, The invention relates to novel compounds of the formula I, wherein R2, R2, R3, R4 and R5 have the meanings given in the description to enol ethers, and salts thereof and their preparation to weed control compositions that comprise such compounds as active ingredients, and to the use of the compounds or compositions to control weeds. The invention relates also to certain novel starting materials and to the preparation thereof.
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 August 29, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 29, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 29, 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.