Process for the preparation of 2-nitro-3- aminopyridine, and n,n'-di-(2-nitro-3-pyridyl)-urea, which is formed as an intermediate in the reaction
CA 1287633 C · Owner: Warning, Klaus · Inventors: Schaeffer, Georg; Herbst, Horst; Planker, Siegfried
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
2-Nitro-3-aminopyridine is prepared by nitrating N,N'-di- (3-pyridyl)-urea, with subsequent hydrolysis. N,N'-Di-(2nitro-3-pyridyl)-urea, which is formed in the course of the reaction as an intermediate, is a new compound. The end product of the process, 2-nitro-3-aminopyridine is, principally an intermediate in various specialized fields for example, in the pharmaceutical, dyestuff and plant protection sectors.
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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
- Granted August 13, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 13, 2008.
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Timeline
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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.