Sulfonyl compound and use of said compound as an intermediate in the process of producing vitamin a or its esters
CA 2039922 A1 · Owner: Bakker, Cees · Inventors: Bakker, Cees; Lagerweij, Gerrit J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract, The invention relates to a new sulfonyl compound having the general formula, (I), wherein R1 is an unsubstituted or substituted aryl group; and, R2 is a C1-C20 alkyl group a C2-C20 alkenyl group, or a C2-C20 alkynyl group which groups may be, substituted with one or more substituents selected from the group consisting of C1-C4 alkoxy, halogen, unsubstituted aryl and substituted aryl; or wherein R2 is a tri- (hydrocarbyl)silyl group, an optionally loweralkyl- substituted dihydro- or tetrahydropyran-2-yl group, an optionally lower- alkylsubstitute dihydro- or- tetrahydro-fur-2-ylgroup, or a lower alkoxyalkylgroup. This sulfonyl compound can be used as an intermediate in the process …
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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 April 5, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 5, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 5, 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.