Preparation of imidazole derivatives for treatment of glaucoma
CA 2018978 C · Owner: Mitsui Petrochemical Industries Ltd. · Inventors: Ori, Aiichiro; Kihara, Noriaki; Imuta, Junichi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Process for preparing imidazole derivatives of the general formula (I), ............. (I) wherein R1 and R2 independently are C1-C4 alkyl by, desulfurizing a mercaptoimidazole derivative of the general formula (I):, ................. (I) wherein R1 and R2 are as defined above uith nitric acid, in the presence of a nitrite. The compounds of the formula(I) are useful for the treatment of glaucoma.
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 14, 1990 and granted February 25, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 14, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 14, 2012.
- 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.