Method for preparing a benzofuran or benzothiophene compound
CA 2387724 C · Owner: Schlama, Thierry · Inventors: Schlama, Thierry
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention concerns a novel method for preparing a benzofuran or benzothiophene compound by cyclizing an aromatic compound bearing a side-chain comprising at least two carbon atoms one of the carbon atoms being bound to the benzene cycle by an oxygen or sulphur atom the other carbon atom is in carboxylic form and a formyl radical in ortho position relative to said chain. The inventive method is characterised in that it consists in cyclizing the latter in the presence of an efficient amount of a carbonate base in a medium comprising a carboxylic acid anhydride and optionally an organic solvent.
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 October 23, 2000 and granted September 20, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 23, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 23, 2022.
- 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.