Two-stage solution polymerization of high molecular weight poly(phosphoesters)
CA 2295209 A1 · Owner: Guilford Pharmaceuticals Inc. · Inventors: Leong, Kam W.; Zhao, Zhong; Mao, Hai-Quan
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for making a phosphoester polymer comprising the recurring monomeric units of formula (I), wherein X is -O- or -NR"where R" is H or alkyl; L is , a divalent organic moiety; R' is H alkyl, alkoxy, aryl, aryloxy, heterocyclic or heterocycloxy; and n is between about 25 to 2,000 is , described. The process comprises the steps of: (a) polymerizing in the presence of a solvent p moles of a di-XH compound having formula (II): H - X - L - X - H wherein X and L are as defined above with q moles, where p q, of a , phosphorodihalo compound to form a polymer of formula (I) wherein n is about , 12 to 1,000, having a first molecular weight Mw1 wherein the solvent is , present in an amount …
Read the whole patent
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 June 17, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 17, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 17, 2020.
- 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.