Preparation of (7s, trans)-2-(2-pyrimidinyl)-7-(hydroxymethyl) octahydro-2h-pyrido1,2-apyrazine
CA 2099563 C · Owner: Pfizer Inc. · Inventors: Murtiashaw, Charles W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for separating the enantiomers (I) (II) of a racemic mixture of trans-2-(2-pyrimidinyl)-7-(hydroxymethyl) octa-hydro-2H-pyrido1,2-apyrazine comprising reacting the racemic mixture with D-(-) or L-( + ) tartaric acid and separating the resulting diastereomeric tartrate salts.
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 December 5, 1991 and granted September 29, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 5, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 5, 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
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.