Purine derivatives
CA 1109872 A · Owner: Bristol-Myers Squibb Company · Inventors: Naito, Takayuki; Okita, Taka-Aki; Nakagawa, Susumu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Pharmaceutical Compounds, Abstract of the Disclosure Purine derivatives of the formula, wherein R is C1-C6 alkyl and R1 is or, and their pharmaceutically acceptable acid addition salts are non-adrenergic bronchodilators. This divisional specification relates particularly to an intermediate compound for the production of these compounds namely, II
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
- Granted September 29, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 29, 1998.
- 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.