Ring-closure method for 1-carbacephalosporin six-membered ring
CA 2066493 A1 · Owner: Eli Lilly And Company · Inventors: Ternansky, Robert J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
X-83276, Abstract, The invention provides a process for preparing 7-protected amino- 4-protected carboxy-1-carbacephalosporins which includes subjecting a 3protected-amino-4-(1-propylene oxide)-methyl(protected carboxy)-azetidin-2one to a strong base to form a 2-hydroxycepham and thereafter dehydrating the 2-hydroxycepham to form the desired 1-carbacephalosporin. Also included in the invention are novel intermediates.
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 April 21, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 21, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 21, 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.