Non-hygroscopic mono-ammonium salts
CA 2084663 C · Owner: Fehervari, Edit · Inventors: Repasi, Janos; Powell, Fulgencio; Gulyas, Imre
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
New, non-hygroscopic, crystalline mono-ammonium salts of general formula (I) where, R1 stands for hydroxy or alkyl; -A stands for 1-4 alkyl-amino- or amino-alkyl-groups containing primary or secondary amino-groups preferably, -CH2-NH- or -CH(NH2)-CH2-groups; B stands for ammonium -ion, or alkyl-substituted ammonium-ion- as well as processes to obtain the same by preparing the mono-ammonium salt of general formula (I) according to any method known, generally for the preparation of salts whereby, along with avoiding other contaminations on the course of or after, salt-formation the di-ammonium salt of general formula (V). where -R1, A and B stand for the above, is eliminated or its formation …
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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 April 15, 1992 and granted December 23, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 15, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 15, 2014.
- 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.