Process for the synthesis of (4r-cis)-1, 1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1, 3-dioxane-4-acetate
CA 2092997 C · Owner: Millar, Alan · Inventors: Millar, Alan; Butler, Donald Eugene
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the preparation of the compound of formula (I) which comprises treating a compound of formula (V) wherein L is halogen or (a), wherein Ar is aryl with a compound of the formula , (VI): M-CN. A second aspect of the present invention is a novel intermediate of formula (V).
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 September 11, 1991 and granted May 14, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 11, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 11, 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.