Fused five-ring heterocyclic compounds, their production, and their pharmaceutical use
CA 1291754 C · Owner: Tomita, Kuniyuki · Inventors: Kumakura, Seiji; Shimoji, Yasuo; Koike, Hiroyuki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
OF TH~ DI8CLOSURE, Fused ring compounds of formula (I): (I), (where R1-R4, X1 and X2 represent hydrogen or various substituents, n and m are 1-3 and 2-7 respectively, the dotted lines are double or single bonds and Y is one oxygen or two hydrogens) have magnificent anti-arrhythmic activity, diuretic activity and the ability to improve brain function.
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
- Granted November 5, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 5, 2008.
- 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.