Process for the preparation of 1,2-benzoxathiine derivatives
CA 1249833 A · Owner: Novartis Pharmaceuticals Canada Inc./Novartis Pharma Canada Inc. · Inventors: Fory, Werner
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Process for the preparation of 1,2-benzoxathiine derivatives Abstract of the Disclosure, A novel process for the preparation of 3,4-dihydro-2,2-dioxo-3methyl-1,2-benzoxathiin-8-ylsulfonamide of formula I (I), reacting a 5-halo-2,3-dihydro-2-methylbenzobfuran of the formula II, (II), wherein Hal is chlorine or bromine with chlorosulfonic acid to give, a 6-halo-2,2-dioxo-3-methyl-1,2-benzoxathiin-8-ylsulfonyl chloride of formula III, (III), wherein Hal is chlorine or bromine converting this sulfonyl, chloride with ammonia into a 6-halo-2,2-dioxo-3-methyl-1,2-benzoxathiin-8-ylsulfonamlde of formula IV (IV), wherein Hal is chlorine or bromine dehalogenating this sulfonamide, with hydrogen in …
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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 February 7, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 7, 2006.
- 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
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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.