Novel cephalosporin antibiotics and processes for the preparation thereof
CA 2117679 C · Owner: Bang, Chan S. · Inventors: Lee, Tae H.; Yang, Deog H.; Kim, Se H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Novel cephalosporin compounds of formula(I): wherein:, R1 is a hydrogen or an amino protecting group; R2 and R3 are, independently, a hydrogen or a hydroxy protecting group, or form together a cyclic diol protecting group;, R4 and R5 are, independently, a hydrogen or a carboxyl protecting group;, X and Y are a nitrogen and a carbon atom respectively, or a, carbon and a nitrogen atom respectively;, R6 and R7 are, independently a hydrogen or an amino, substituted amino hydroxy, alkoxy, C1-4 alkyl, carboxyl or alkoxy carbonyl group, or jointly form a C3-7 cycloalkyl group together with the carbon to which they are attached when X, and Y are a nitrogen and a-carbon respectively, or R7 is a, …
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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 September 9, 1994 and granted March 7, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 9, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 9, 2016.
- 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.