Synthesis of combretastatin a-2 prodrugs
CA 2471309 A1 · Owner: Arizona Board Of Regents · Inventors: Petit, George R.; Moser, Bryan R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The original synthesis of combretastatin A-2 (1a) was modified to provide an efficient scale-up procedure for obtaining this antineoplastic stilbene. Subsequent conversion to a useful prodrug was accomplished by phosphorylation employing in situ formation of dibenzylchlorophosphite followed 30 by cleavage of the benzyl ester protective groups with bromotrimethylsilane to afford phosphoric acid intermediate 11. The latter was immediately treated with sodium methoxide to complete a practical route to the disodium phosphate prodrug (2a). The phosphoric acid precursor (11) of phosphate 2a was employed in a parallel series of reactions to produce a selection of metal and ammonium cation …
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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 20, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 20, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 20, 2024.
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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.