Processes for preparation of 9,11-epoxy steroids and intermediates useful therein
CA 2550897 A1 · Owner: Anderson, Dennis K. · Inventors: Erb, Bernhard; Wang, Ping T.; Letendre, Leo J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Multiple novel reaction schemes, novel process steps and novel intermediates are provided for the synthesis of epoxymexrenone and other compounds of Formula I (see formula I), wherein:, -A-A- represents the group -CHR4-CHR5- or CR4=CR5-; R3, R4 and R5 are independently selected from the group consisting of hydrogen, halo, hydroxy lower alkyl, lower alkoxy, hydroxyalkyl alkoxyalkyl, hydroxycarbonyl, cyano, aryloxy; R1 represents an alpha-oriented lower alkoxycarbonyl or hydroxyalkyl radical;, -B-B- represents the group -CHR6-CHR7- or an alphaor beta- oriented group:, (see formula III) where R6 and R7 re independently selected from the group consisting of hydrogen, halo, lower alkoxy acyl, …
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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 December 11, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 11, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 11, 2019.
- 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.