Isolation and purification of paclitaxel and cephalomannine
CA 2210972 C · Owner: Xechem International, Inc. · Inventors: Yankov, Luben K.; Pandey, Ramesh C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A novel process for extraction, isolation and separation of taxanes particularly paclitaxel, from natural sources such as bark needles, and twigs from Taxus species, tissue cultures and fungi is described, wherein the taxanes are separated from the crude extracts by partitioning between polar and nonpolar solvents precipitation in nonpolar solutions, reacting the mixture by halogenation of unsaturated taxane derivatives, followed by chromatographically separating and crystallizing taxanes from a mixture of polar and nonpolar solvents; more particularly, the process of halogenation of unsaturated side chain taxane derivatives particularly cephalomannine in presence of paclitaxel, is …
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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 November 1, 1996 and granted October 21, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 1, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 1, 2018.
- 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
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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.