Manufacture of 3-halosulfonylthiophene-carboxylic acid compounds
CA 1097358 A · Owner: Basf Aktiengesellschaft · Inventors: Hoffmann, Werner; Mueller, Norbert; Rossy, Phillip A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
O.Z. 32,364/542, ABSTRACT OF THE DISCLOSURE: 3-Halosulfonylthiophene-carboxylic acid compounds are manufactured by reacting 3-ketothiophane-carboxylic acid compounds with sulfonic acid compounds reacting the, end product from the 1st reaction stage with alkali metal polysulfides, reacting the end product from the 2nd stage with a dehydrogenating agent and finally reacting the end product from the 3rd stage with halogen and water. The products are starting compounds for the manufacture of drugs dyes and crop protection, agents and have an anti-inflammatory analgesic and anti-rheumatic, action. In particular the end products I are starting materials for the manufacture of sweeteners which 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
- Granted March 10, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 10, 1998.
- 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.