Process for the preparation of 4-acyloxy-2-azetidinone derivatives
CA 2000565 C · Owner: Ishiguro, Masaji · Inventors: Iwata, Hiromitsu; Nakatsuka, Takashi; Yamada, Yasuo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a process for preparing a 4-acyloxy- 2-azetidinone derivatives of the following formula: wherein OR is a protected hydroxy group and Y is an acyl group, which comprises reacting a 2-azetidinone derivative of the following formula:, wherein OR has the same meaning as defined above and X is an alkyl group or an aromatic group,and a copper oxide or copper salt of an organic carboxylic acid,in the presence of an organic carboxylic acid or a salt of an organic carboxylic acid as an acyl group source. The process is an effective route for producing 3-1'-(R)-hydroxyethyl-4-acyloxyazetidinone, an intermediate for synthesizing penems or carbapenems, without using a mercury salt which …
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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 October 12, 1989 and granted June 23, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 12, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 12, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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.