Pyridonecarboxylic acid derivatives
CA 2076982 A1 · Owner: Arakawa, Hiroharu · Inventors: Ushijima, Ryosuke; Nakagawa, Susumu; Yoshinari, Tomoko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to compounds represented by the following general formula or their pharmaceutically acceptable salts or esters, a process for preparation thereof and antitumor agents containing them as an effective ingredient III, wherein R1 represents a straight- chain branched or cyclic lower, alkyl group or a phenyl group optionally substituted by fluorine atom(s), R2 and R3 each represent a hydrogen atom or a straight - chain, branched or cyclic lower alkyl group R1 represents a, hydrogen atom or -N (R5) R6 wherein R5 and R6 each represent a hydrogen atom or a straight-chain, branched or cyclic lower alkyl group, X represents a nitrogen atom or C - Y wherein Y represents a …
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 November 29, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 29, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 29, 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.