Synthesis of hydroxysulfone and related compounds
CA 2229233 C · Owner: Mathre, David J. · Inventors: Mathre, David J.; Sohar, Paul; Blacker, Andrew J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention is concerned with an improved process for the synthesis of hydroxysulfone, which is a key intermediate in the synthesis of carbonic anhydrase inhibitors, especially dorzolamide. Carbonic anhydrase inhibitors are known to be effective in treating elevated intraocular pressure or glaucoma.
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 August 26, 1996 and granted October 7, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 26, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 26, 2018.
- 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.