Process for the preparation of 4-methyl-7-aminoquinolones
CA 2467511 A1 · Owner: Ciba Specialty Chemicals Holding Inc. · Inventors: Lamatsch, Bernd; Benkhoff, Johannes
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to a process for the preparation of a compound of the general formula (I), which comprises converting a compound of the general formula (II), in an aprotic organic solvent in the presence of a catalytically active amount of a strong acid (catalyst) or of an agent that liberates a strong acid or of an ammonium salt of a strong acid it also being , possible for the catalyst to be part of the starting material/product into a , compound of formula I, wherein R5 R6 and R8 are each independently of the others a hydrogen atom, a nitro group, a sulfo group a halogen atom, a , pseudohalogen, a group COOR1 or CONHR2 or a C1-8 alkyl C1-8 alkoxy or aryloxy , radical, …
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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 3, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 3, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 3, 2024.
- 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.