Quinone derivatives, their production and use
CA 1285280 C · Owner: Takeda Chemical Industries, Ltd. · Inventors: Maki, Yoshitaka; Terao, Shinji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Quinone derivatives of the general formula: (I), (wherein R1 and R2 are the same or different and independently, are a hydrogen atom or a methyl or methoxy group or R1 and, R2 combine with each other to represent -CH=CH-CH=CH-; R3 is a hydrogen atom or a methyl group; R4 is an aliphatic aromatic or heterocyclic group which may be substituted; R5 is a methyl or methoxy group, a hydroxymethyl group which may be susbtituted or a carboxyl group which may be esterified or amidated; Z is a group represented by -C?C- -CH=CH-, , , , or , ; n is an integer of 0 to 10; m is an integer of 0 to 3; k is an integer of 0 to 5 provided, however, that in the case of m being 2 or 3 Z, and k can vary …
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 June 25, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 25, 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.