Preparation of warfarin sodium from warfarin acid
CA 2438407 A1 · Owner: Ashkar, Michel · Inventors: Bercovici, Sorin; Ashkar, Michel; Graf, Robert
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention provides a method for the direct preparation of pure warfarin sodium from warfarin acid. The reaction is conducted in a polar organic solvent, preferably ethanol, using a volatilizable base preferably sodium , bicarbonate or sodium carbonate at low temperature. Drying the final product is accomplished at low temperature to avoid decomposition of the final warfarin sodium product.
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 December 28, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 28, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 28, 2023.
- 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.