N-substituted chitosan derivatives, process for their preparation and the use thereof
CA 2092513 A1 · Owner: Lohmann, Dieter · Inventors: Lohmann, Dieter; Randell, Donald R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
FL/6-19038/A, N-Substituted chitosan derivatives process for their preparation and the use thereof Abstract of the Disclosure, Chitosan derivatives having structural units of formula I II and III in random distribution, , (I) (II) (III) wherein the substituents R1 are each independently of one another H or the radical -Z-R2-X, R3 is H or acetyl, Y is the anion O-Z-R2-X and, (a) Z is -CO- or -SO2-, X is -CO2H -CH2CO2H or -CH2PO(OH)2, and R2 is, -CHR4CR5(OH)- R4 is -H, -OH, C1-C4alkoxy or C1-C4alkyl and R5 is H or C1-C4alkyl, or, (b) Z is -CO- X is -CO2H, and R2 is -CHR6-CHR7-CH(OH)- or -CHR8-CHR9-CHR10-CH(OH)-, R6, R7, R8 and R10 are each independently of one another -H, -OH, C1-C4alkyl or …
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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 March 25, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 25, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 25, 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
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Sources & verification
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.