Dihydropyridine derivatives and pharmaceutical compositions
CA 2028394 A1 · Owner: The Green Cross Corporation · Inventors: Fukaya, Chikara; Ohtaki, Yutaka; Yokoyama, Kazumasa
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Dihydropyridine derivatives of the formula wherein R1, R2 and R3 are the same or different and each is, alkyl, cycloalkyl or alkoxyalkyl; R4 and R5 are the same or different, and each is hydrogen atom, halogen nitro, haloge-, nated alkyl, alkylsulfonyl halogenated alkoxy, alkylsulfi-, nyl, alkyl cycloalkyl, alkoxy, cyano, alkoxycarbonyl or alkylthio (wherein both of R4 and R5 are not hydrogen atoms at the same time); X is a group represented by vinylene or azomethine; A is alkylene; B is -N(R6)2 or (wherein R6 and R7 are independently hydrogen atom alkyl, cycloalkyl, aralkyl, aryl or pyridyl Ar is aryl or pyridyl, and n is an integer of 0 to 2) acid addition salts thereof, and …
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 October 24, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 24, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 24, 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.