Novel methylenebisphosphonic acid derivatives
CA 2098735 C · Owner: Hanhijarvi, Hannu · Inventors: Hanhijarvi, Hannu; Nikander, Hannu; Pohjala, Esko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Novel pharmacologically active methylenebisphosphonates having formula (I) wherein R1-R4 independently are, C1-C10-alkyl C3-C10-cycloalkyl, aryl, aralkyl, silyl SiR3 or hydrogen whereby in formula (I) at least one of the groups R1-R4 is hydrogen and at least one of the groups R1-R4 is different from hydrogen; Q1 is hydrogen, hydroxyl, halogen ami-, no NH2, or OR'1, wherein R'1 is C1-C4-alkyl or acyl; Q2 is the group,(.alpha.) wherein Y is a six-membered heterocyclic group or a, carbocyclic aromatic group, X is a bond O, S or NR"', wherein R"' is , hydrogen lower alkyl, or acyl, n is the integer 0 to 6 and, R' and R" are hydrogen or lower alkyl provided that as a ring atom of the ring Y …
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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 18, 1991 and granted March 5, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 18, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 18, 2013.
- 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
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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.