Process for the preparation of 4-hydroxy-3-2h furanones
CA 2077965 C · Owner: Givaudan Roure B.V. · Inventors: Van Ek, Cees; Lenselink, Willem; Cohen, Amnon M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention is directed to a process for the preparation of 5-alkyl-4-hydroxy-32Hfuranones and/or 2,5-dialkyl-4-hydroxy- 32Hfuranones, wherein each alkyl group independently has one to six carbon atoms, comprising;, (a) saponification of an ester selected from the group of 3,4-dihydroxyfurans substituted at the 2- and/or 5-position with one or two carbalkoxy groups, wherein each alkoxy group independently contains one to six carbon atoms and optionally, substituted at the 2- or 5-position with an alkyl group with one to six carbon atoms, or tautomeric forms or keto-enol isomers thereof,. (b) subsequent treatment with one or two alkylation reagents which independently may have one to six …
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 10, 1992 and granted April 8, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 10, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 10, 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.