Process for preparing granisetron
CA 2481703 A1 · Owner: Laboratorios Vita, S.A. · Inventors: Puig Torres, Salvador; Dalmases Barjoan, Pere
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a process for preparing granisetron or a , pharmaceutically acceptable salt thereof which comprises: a) cyclisation of a , compound of formula (I) in an inert solvent and at a temperature between 0- 100~C, in the presence of a strong acid in order to yield the compound of , formula (II); b) methylation of the compound of formula (II) with an , alkylating agent, in the presence of a base in an inert solvent and at a , temperature between 0~C-160~C and with optional formation of a , pharmaceutically acceptable salt.The process of the invention yields a granisetron of high purity, preventing impurities due to demethylation by , carrying out the methylation after …
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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 March 21, 2003. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 21, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 21, 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.