Process for producing halogenated heteroaryl compounds
CA 2274597 C · Owner: Ishikawa, Kiyofumi · Inventors: Ushijima, Ryosuke; Okada, Shigemitsu; Ishikawa, Kiyofumi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for producing compounds represented by general formula (II) wherein , X represents halogeno; A1, A2 and A3 are the same or different and each represents carbon or nitrogen, provided that at least one of A1 A2, and A3 is , nitrogen; and R1, R2, R3 and R4 are the same or different and each represents hydrogen, lower alkyl, cyano, carboxy, lower alkyloxycarbonyl carbamoyl, halogeno, nitro, hydroxy, or lower aminoalkyl provided that when R1 and R2 , are adjacent substituents the two can be bonded to each other to form a five- or six-membered ring optionally having on the ring one substituent selected from the group consisting of lower alkyl nitryl, carboxy, lower , …
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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
- Filed December 9, 1997 and granted February 11, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 9, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 9, 2019.
- 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.