Asymmetric synthesis of piperazic acid and derivatives thereof
CA 2403304 A1 · Owner: Stibbard, John · Inventors: Dieterich, Petra; Stibbard, John; Robidoux, Andrea
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention provides a short, asymmetric synthesis of piperazic acid and derivatives thereof, whereby either the (3S)- or (3R)-enantiomeric form may be obtained with high optical purity. (3S)-piperazic acid is derived from Dglutamic acid through an (R)-2, 5-dihydroxyvalerate ester intermediate. After the hydroxy groups are converted to suitable leaving groups,such as mesylates the ester is treated with a bis-protected hydrazine to provide the desired (3S)-piperazic acid derivative. The (3R) enantiomer of piperazic acid may be similarly obtained starting with L-glutamic acid. The method may also be used to obtain piperazic acid derivatives that have moderate optical purity or are …
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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 April 25, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 25, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 25, 2023.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.