US3726875A
Expired / Lapsed
US
⏱️ 0.0 years remaining
1,3(2h,4h)-dioxoisoquinoline-4-carboxylate esters and process therefor
Assignee: Pfizer Inc
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Filing: 1971-02-05
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Granted: 1973-04-10
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Expires: 1991-02-05
Abstract
Abstract 1,3(2H,4H)-DIOXOISOQUINOLINE-4-CARBOXAMIDES, NUCLAR UNSUBSTITUTED AND SUBSTITUTED, ARE PREPARED BY REACTING THE APPROPRIATE HOMOPHTHALIMIDE WITH POTASSIUM CYANATE. SECONDARY CARBOXAMIDES ARE PREPARED BY REACTING HOMOPHTHALIMIDE WITH APPROPRIATE ISOCYANATES, AND TERTIARY CARBOXAMIDES ARE PREPARED BY AMINOLYSIS OF 4-CARBALKOXY COMPOUNDS, WHICH ARE, IN TURN, PREPARED BY ALCOHOLYSIS OF THE CORRESPONDING 4-CARBOXANILIDES. CORRESPONDING 5.6, 78,-TETRAHYDRO COMPOUNDS ARE SIMILARLY PREPARED. HE VARIOUS 2-SUBSTITUTED HOMOPHTHALIMIDES ARE PREPARED BY EACTING HOMOPHTHALIC ACID WITH AN APPROPRIATE AMINE. THE 4-CARBOXAMIDES ARE ANTI-INFLAMMATORY AGENTS.
Inventors
- 👤 S Kadin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:52
CPC Classifications
C; C07; C07D; C07D217/00; C07D217/22; C07D217/24; C07D217/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-09 | 1976-10-09 | 1977-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-09 | 1980-10-09 | 1981-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-09 | 1984-10-09 | 1985-04-10 | $7700.00 | Window Closed / Lapsed |