Use of aromatic hydrocarbons and silicone fluids for making disphosphonic acids
CA 2657002 A1 · Owner: Teva Pharmaceutical Industries Ltd. · Inventors: Harel, Zvi; Kovalevski-Ishai, Eti; Lifshitz-Liron, Revital
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Provided is a novel method of making bisphosphonic acids e.g. risedronic , acid, including , the step of combining a carboxylic acid phosphorous acid, and a , halophosphorous compound in the presence of a diluent that is an aromatic hydrocarbon or a silicone fluid. , When the diluent is an aromatic hydrocarbon an inert support or ortho-, phosphoric acid codiluent is advantageously included.
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 May 19, 2003. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 19, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 19, 2025.
- 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.