Pyridylsulfonylureas as herbicides and plant growth regulators, processes for their preparation and their use
CA 2073446 C · Owner: Willms, Lothar · Inventors: Willms, Lothar; Bieringer, Hermann; Bauer, Klaus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Compounds of formula (I), where R1, R2 n, W, R3 and A are as defined in claim 1, are suitable for use as herbicides, and plant growth regulators. They can be produced by a process similar to known processes. To produce them, new compounds of formula (II) are reacted with a carbamate of formula R*-O-CO-NR3A where R3 stands for phenyl or alkyl. The compounds of formula (II) can be obtained from the corresponding sulphochlorides.
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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 December 24, 1990 and granted November 27, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 24, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 24, 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.