Improved methods for h-phosphonate synthesis of mono- and oligonucleotides
CA 2205218 C · Owner: Hybridon, Inc. · Inventors: Bhongle, Nandkumar
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
New methods of synthesizing mono- and oligo- nucleotide H-phosphonates are disclosed. The methods comprise contacting a mononucleoside with phosphonic acid and benzoyl anhydride or propane phosphonic acid anhydride to yield the corresponding mononucleoside H-phosphonate. Preferably a catalytic amount of triphosgene is also used. A similar procedure can be used to couple a first mononucleoside to a second mononucleoside or to an oligonucleotide the method comprising contacting, in the presence of benzoic anhydride or propane phosphonic acid anhydride and preferably, when benzoic, anhydride is used a catalytic amount of triphosgene, a mononucleotide or oligonucleotide having a free 5' …
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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 18, 1996 and granted May 25, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 18, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 18, 2018.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.