Process for the production of 4-amino-1-hydroxybutylidene-1,1-bisphosphonic acid or salts thereof
CA 2197267 C · Owner: Apotex Technologies Inc. · Inventors: Tao, Yong; Kubela, Rudolf
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process is provided for the preparation of 4-amino-1-hydroxybutylidene- 1,1-bisphosphonic acid or salts thereof which comprises of: a) reacting 4-aminobutyric acid with phosphorous acid and phosphorus trichloride in the presence of a polyalkylene(glycol); and b) recovering said 4-amino-1-hydroxybutylidene-1,1-bisphosphonic acid or salts thereof.
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 11, 1997 and granted February 8, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 11, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 11, 2019.
- 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.