Process for the preparation of dialkyl, pyridine-2,3-dicarboxylates and derivatives thereof from dialkyl dichlorosuccinate
CA 2044498 C · Owner: Chiarello, George Anello · Inventors: Cevasco, Albert Anthony; Rieker, William Frederick; Chiarello, George Anello
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
There is provided a process for the preparation of substituted and unsubstituted-2,3-pyridinedicarboxylate compounds by reacting a dialkyl dichlorosuccinate with a dehydrohalogenating agent, an ammonia source and an appropriately substituted .alpha..beta.-unsaturated aldehyde or ketone.
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 June 13, 1991 and granted June 11, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 13, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 13, 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.