Production of crystalline penem
CA 2078601 A1 · Owner: Takeda Chemical Industries, Ltd. · Inventors: Yabuno, Shigeo; Kaneko, Masayoshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a method of crystallizing (1R,5S,6S)-2- (6,7-dihydro-5H-pyrazolo1,2-a1,2,4triazolium-6-yl)thio-6- (R)-1-hydroxyethyl-1-methyl-carbapenem-3-carboxylate (hereinafter simply referred to as L-627), by maintaining an aqueous solution of L-627 at a temperature in the range from the eutectic temperature of the solution to a temperature lower than 0°C. The method provides such advantages that loss of L-627 accompanied by crystallization is reduced, the number of steps in the preparation of vial formulations is small and maintenance of these steps under sterile and dust-free conditions can be performed easily, dispensing of the drug can be conducted with quantitative accuracy, and the …
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 September 18, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 18, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 18, 2014.
- 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.