Process for resolution of racemates of 2,2-dimethylcyclopropanecarboxylic acid
CA 2044570 A1 · Owner: Lonza Ltd. · Inventors: Meul, Thomas
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process is disclosed for preparing optically pure 2,2-dimethylcyclopropanecarboxylic acid in which the, enantiomers are separated from the racemate by esterification with the hydroxy group of optically active mandelic acid methyl ester, crystallization of the diastereomeric esters and subsequent hydrolysis of the diastereomeric esters.
Read the whole patent
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 June 13, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 13, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 13, 2013.
- 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.