2,3(1h,4h)-quinoxalinediones
CA 2097141 A1 · Owner: Hofmann, Hans Peter · Inventors: Behl, Berthold; Lubisch, Wilfried; Hofmann, Hans Peter
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
O.Z. 0050/43262, Abstract of the Disclosure: 2,3(1H,4H)-quinoxalinediones of the formula I, I, where, R1 is hydrogen an aliphatic radical which has up to 12 carbons and can be substituted by one of the following: phenyl, cyclopentyl, cyclohexyl or -CO-R3 -CO-O-R3 or, -Co-NH-R3, where R3 is hydrogen C1-C4-alkyl, phenyl, benzyl or 1-phenylethyl a cycloaliphatic radical with up to 12 carbons or phenyl where the cyclic groups in R1 can have up to three of the following substituents: C1-C4-alkyl, C1-C4-haloalkyl C1-C4-alkoxy, C1-C4-haloalkoxy, halogen nitro, cyano, -CO-O-R3 and -CO-NH-R3;, R2 is 1-pyrrolyl which can have up to two of the following substituents: C1-C4-alkyl, phenyl, …
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 May 27, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 27, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 27, 2015.
- 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.