Process for the preparation of pure citalopram
CA 2360303 C · Owner: Villa, Marco · Inventors: Villa, Marco; Sbrogio, Federico; Dancer, Robert
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to a process for the preparation and purification of citalopram (I) in which a compound of Formula (II) wherein Z is iodo, bromo, chloro or CF3-(CF2)n -SO2-On being 0, 1, 2, 3, 4, 5, 6, 7 or 8, is subjected to a cyanide exchange reaction with a cyanide source; the resultant crude citalopram product is optionally subjected to some initial purification and subsequently treated with an amide or an amide-like group forming agent; the reaction mixture is then subjected to an acid/base wash and/or crystallisation and recrystallisation of citalopram in order to remove the amides formed from the crude citalopram mixture; and the resulting citalopram product is …
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 March 7, 2001 and granted August 12, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 7, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 7, 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.