Process for the preparation of citalopram
CA 2438650 A1 · Owner: Venkaiah, Chowdary Nannapaneni · Inventors: Pulla, Reddy Muddasani; Venkaiah, Chowdary Nannapaneni
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention discloses an improved process for the preparation of citalopram of the formula III which comprises (i) preparing the compound of the formula VIII by reducing an unisolable magnesium salt of a benzophenone derivative of the formula V using sodium borohydride in the presence of a protic solvent (ii) reacting the compound of the formula VIII obtained in step (i) with an acid catalyst in a non-polar solvent to obtain a compound of the formula I (iii) reacting the compound of the formula I obtained in step (ii) with copper (I) cyanide in a polar solvent medium and isolating the resulting cyano compound, by recrystallization by using polar and/or alcoholic solvents to obtain …
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, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 11, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 11, 2024.
- 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.