Methods of making indazoles
CA 2447482 A1 · Owner: Pierce, David R. · Inventors: Dean, William D.; Delgado, Pete; Pierce, David R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Methods of making indazoles are described. The methods involved reacting an aromatic aldehyde with a nitrogen source to form a nitroso aromatic aldehyde. The nitroso aromatic aldehyde is reacted with a reducing agent to form an indazole which ultimately can be used to form desired indazoles which are preferably pharmaceutically active products. The process of the present invention further permits the formation of enantiomerically enriched or pure indazoles such as aminoalkyl indazoles.
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 May 30, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 30, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 30, 2024.
- 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.