Process for the preparation of 1-(mercaptomethyl)-cyclopropaneacetic acid
CA 2371048 C · Owner: Zhou, Zhihong · Inventors: Zhou, Zhihong; Wang, Yuan; Harper, Sylvain
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the preparation of highly pure 1-(mercaptomethyl)cyclopropaneacetic acid , is described. Treatment of 1-(hydroxymethyl)-cyclopropaneacetonitrile with an acid , provides the corresponding imino ester and/or halo-amide which when reacted , with , thiourea provide the corresponding amide-isothiuronium salt. Hydrolysis of the amide-isothiuronium salt followed by an in situ oxidation allows the facile isolation and , purification of 1-1-(carboxymethyl)-cyclopropanemethyldisulfanylmethylcyclopropaneacetic, acid (also known as 1-(mercaptomethyl)-cyclopropaneacetic acid disulfide). Reduction of the 1-(mercaptomethyl)-cyclopropaneacetic acid disulfide under , mild conditions …
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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 February 6, 2002 and granted January 4, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 6, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 6, 2024.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.