Process for the optical resolution of threo-2-hydroxy-3-(2'-aminophenylthio)-3-(4"methoxy-phenyl) -propionic acid
CA 2030375 A1 · Owner: F I S - Fabbrica Italiana Sintetici S.P.A. · Inventors: Rizzi, Amleto; Marchioro, Gaetano
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
PROCESS FOR THE OPTICAL RESOLUTION OF THREO-2-HYDROXY-3- (2'-AMINOPHENYLTHIO)-3-(4"-METHOXYPHENYL)-PROPIONIIC ACID" Abstract, The present invention relates to a process for the separation of the enantiomers of threo-2-hydroxy-3-(2'aminophenylthio)-3-(4"-methoxyphenyl)-propionic acid which is an important intermediate in the synthesis of pharmacologically active compounds, by means of the direct crystallization of the relevant cyclohexylaminic salt. According to a preferred form of practical embodiment of the present invention, the optically pure acid is recovered as the hydrochloride of the corresponding methyl ester
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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 November 20, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 20, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 20, 2012.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.