US2648682A
Expired / Lapsed
US
⏱️ 0.0 years remaining
3-substituted 4-hydroxycoumarins and process for their production
Assignee: Novartis AG
•
Filing: 1951-01-03
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Granted: 1953-08-11
•
Expires: 1971-01-03
Abstract
No abstract record available.
Inventors
- 👤 Stoll Willy
- 👤 Litvan Franz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:00
CPC Classifications
C; C07; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/42; C07D311/44; C07D311/46
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
7 words
DERIVATIVES OF 4-HYDROXYCOUMARIN OF THE GENERAL FORMULA:
Claim 2
Dependent Claim
7 words
DERIVATIVES OF 4-HYDROXYCOUMARIN OF THE GENERAL FORMULA:
References Cited (Backward Citations)
US2427578A
Cited
US2427579A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-08-10 | 1957-02-09 | 1957-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-08-10 | 1961-02-09 | 1961-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-08-10 | 1965-02-09 | 1965-08-11 | $7700.00 | Window Closed / Lapsed |