6,7-dialkoxy-3,4-dihydroisoquinolin-8-ol, process for preparation thereof and process for preparation of 6,7-dialkoxy-1,2,3,4-tetrahydroisoquinolin-8-ol using the compound
CA 2116294 A1 · Owner: Banyu Pharmaceutical Co. Ltd. · Inventors: Ishikawa, Kiyofumi; Hayama, Takashi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to novel 6 7 - dialkoxy - 3, 4 -, dihydroisoquinolin - 8 - ols a process for preparing the 6, 7 -, dialkoxy - 3 4 - dihydroisoquinolin - 8 - ols reioselectively and in a high yield utilizing the Bischler - Napieralski reaction a process for, synthesizing 6, 7 - dialkoxy - 1 2, 3, 4 - tetrahydroisoquinolin - 8 - ols via the compounds, and use of the 6, 7 - dialkoxy - 3 4 -, dihydroisoquinolin - 8 - ols for preparation of the 6 7 - dialkoxy - 1, 2, 3, 4 - tetrahydroisoquinolin - 8 - ols. It is possible according to this invention, to obtain the 6 7, - dialkoxy - 1, 2, 3, 4 - tetrahydroisoquinolin - 8 - ols which have, hitherto been difficult to synthesize via the 6, 7 - …
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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 February 23, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 23, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 23, 2016.
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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.