Expired Canadian patentCanada
Synthesis intermediates used in the preparation of 5,6-dihydroxyindole and its 3-alkyl derivative
CA 1300643 C · Owner: Junino, Alex · Inventors: Vandenbossche, Jean-Jacques; Junino, Alex; Lang, Gerard
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
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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 May 12, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 12, 2009.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledNovember 9, 1987
GrantedMay 12, 1992
Term endedMay 12, 2009
Patent numberCA 1300643 C
Classification (IPC)C07C255/43 +2 more
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.