Substituted acyl derivatives of 1,2,3,4-tetrahydroisoquinoline- 3-carboxylic acids
CA 1331614 C · Owner: Klutchko, Sylvester · Inventors: Klutchko, Sylvester; Hoefle, Milton L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to substituted acyl derivatives of 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid compounds having the formula, (I) The invention further relates to the isomers which are S,S,S at the three asymmetric centers identified with asterisks in the formula shown above. Compositions prepared from the invention are useful in treating hypertension.
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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 June 23, 1992 and granted August 23, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 23, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 23, 2014.
- 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.