3(2h)pyridazinone, process for its preparation and anti-allergic agentcontaining it
CA 1297876 C · Owner: Mutsukado, Motoo · Inventors: Mutsukado, Motoo; Tanikawa, Keizo; Sakoda, Ryozo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A 3(2H)pyridazinone of the formula: (I), wherein R1 is hydrogen or C1-C5 alkyl; R2 is hydrogen C1-C8, alkyl, chlorine or bromine; A is -NR3- or -O-; X is (CH2)n- -CH(OR4)-, -CO- or a single bond; when X is -(CH2)n- or a single bond, B is O-, -S-, -NH-, -OSO2or -OCO- or a, single bond, when X is -CH(OR4)- B is -O-, -S-, -NH- or -, OSO2-, and when X is -CO- B is -O- or -S-; and each of Y1, Y2 and Y3 which may be the same or different is hydrogen, C1-C8 alkyl, C2-C8 alkenyl halogen, -OR5, -CO2R6, -, CH=CHCO2R7, -CON(R8)(R9), -COR10, or two of Y1, Y2 and Y3 together form , and a pharmaceutically acceptable salt thereof. Compounds of the formula (I) as defined above are useful for reducing the …
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 March 24, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 24, 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.
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.