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US2777859A
Expired / Lapsed
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Warfarin-alkali metal derivatives and processes of preparing the same
Assignee: Wisconsin Alumni Research Foundation
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Filing: 1953-02-05
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Granted: 1957-01-15
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Expires: 1973-02-05
Abstract
No abstract record available.
Inventors
- 👤 Link Karl Paul
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:10
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
61 words
IN THE PROCESS OF PREPARING AN AQUEOUS SOLUTION OF WARAFARIN-ALKALI METAL DERIVATIVE, THE IMPROVEMENT WHICH COMPRISES SLOWLY ADDING WITH STIRRING AQUEOUS ALKALI METAL HYDROXIDE TO AN EXCESS OF WATER WET WARFARIN, WARMING THE RESULTING AQUEOUS REACTION MIXTURE CONTAINING WARFARIN-ALKALI METAL DERIVATIVE IN SOLUTION IN THE PRESENCE OF THE EXCESS WARFARIN IN SUSPENSION, AND THEN REMOVING THE EXCESS WARFARIN FROM THE SOLUTION.
Claim 2
Dependent Claim
61 words
IN THE PROCESS OF PREPARING AN AQUEOUS SOLUTION OF WARAFARIN-ALKALI METAL DERIVATIVE, THE IMPROVEMENT WHICH COMPRISES SLOWLY ADDING WITH STIRRING AQUEOUS ALKALI METAL HYDROXIDE TO AN EXCESS OF WATER WET WARFARIN, WARMING THE RESULTING AQUEOUS REACTION MIXTURE CONTAINING WARFARIN-ALKALI METAL DERIVATIVE IN SOLUTION IN THE PRESENCE OF THE EXCESS WARFARIN IN SUSPENSION, AND THEN REMOVING THE EXCESS WARFARIN FROM THE SOLUTION.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-01-15 | 1960-07-16 | 1961-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-15 | 1964-07-16 | 1965-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-15 | 1968-07-16 | 1969-01-15 | $7700.00 | Window Closed / Lapsed |