Heterocyclic compounds
CA 2117179 A1 · Owner: Hudson, Alan T. · Inventors: Hudson, Alan T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to novel naphthoquinones of formula (I) wherein R3 is a C1-35 non-aromatic hydrocarbon residue optionally substituted by one or more substituents selected from halo, C1-6 alkoxy, hydroxy, phenyl, phenyl-C1-6alkoxy and phenyl-C1-6alkyl, each such phenyl group or mainly being optionally substituted by one or more groups selected from C1-6alkoxy C1-6alkyl, C1-6alkoxy-C1-6alkyl, hydroxy halogen, halo-C1-6alkyl, amine and mono- or di-C1-4alkyl-amino; and either the dotted line represents a double bond between the 2 and 3 positions of the naphthyl ring, R1 and R4 each represents =O and R2, represents a phosphate group (.alpha.) wherein R5 and R6 which may be the same …
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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 October 8, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 8, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 8, 2014.
- 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.