Benzocycloalkenecarboxylic acid and process for it's preparation
CA 2055602 A1 · Owner: Wetter, Hansjurg · Inventors: Von Sprecher, Andreas; Wetter, Hansjurg
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
4-18007/=, Novel benzocycloalkenecarboxylic acid and process for its preparation Abstract, The novel (S)-4-(2-bromobenzoyl)-5-hydroxy-benzocyclobutene-1-carboxylic i.e. the compound of the formula (I), in free form or in salt form, can be used as active ingredient in pharmaceuticalpreparations and can be prepared by a novel process which is characterised in that, racemic 4-(2-bromobenzoyl)-5-hydroxy-benzocyclobutene-1-carboxylic acid is reacted at elevated temperature with at least the equimolar amount of quinine in an alcoholic solvent for from approximately 6 to approximately 48 hours the quinine salt of the, (S)-4-(2-bromobenzoyl)-5-hydroxy-benzocyclobutene-1-carboxylic acid precipitated …
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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 19, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 19, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 19, 2013.
- 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.