A process for preparing carbamazepine from iminostilbene
CA 2262159 C · Owner: Kulkarni, Ashok Krishna · Inventors: Kulkarni, Ashok Krishna; Vyas, Ketan Dhansukhlal; Jafri, Wajjid Sajjad
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for preparing carbamazepine from iminostilbene is disclosed. The iminostilbene is reacted with urea in a protonating medium. This process results in improvements over prior art processes involving iminostilbene. Carbamazepine is a known muscle relaxant anticonvulsant and antidepressant drug.
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 February 18, 1999 and granted October 21, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 18, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 18, 2021.
- 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.