Process for the production of polymorph of cimetidine
CA 1096387 A · Owner: Smith Kline & French Laboratories Limited · Inventors: Tovey, Geoffrey D.; Bavin, Patrick M.G.; Ward, Richard J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process is provided for the production of a substantially crystallographically pure polymorphic form of cimetidine having the structural formula, Such cimetidine is characterized by an infra red spectrum (1% KBr disc) having very strong, broad peaks at 1400 and 1385 cm-1 a strong, sharp, peak at 1205 cm-1 and a medium-sharp peak at 1155 cm01 and having no peak at 1180 cm-1. The process includes dissolving cimetidine in a hot non-, aqueous solvent, e.g. acetonitrile acetone, methylisobutylketone, toluene or a lower alkanol. The resultant solution is cooled with sufficient agitation to ensure efficient heat transfer to yield a suspension of cimetidine A in the solvent. The suspension is now …
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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 February 24, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 24, 1998.
- 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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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.