US2731497A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of tetracycline
Assignee: Wyeth Holdings LLC
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Filing: 1954-05-14
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Granted: 1956-01-17
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Expires: 1974-05-14
Abstract
No abstract record available.
Inventors
- 👤 Jerry R D Mccormick
- 👤 Smith Neva-Tay Kathleen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:31
CPC Classifications
C; C07; C07C; C07C237/00; C07C237/24; C07C237/26; B; B01; B01J; B01J2231/00; B01J2231/60; B01J2231/64; B01J2231/641; B01J2231/645; C07C2603/00; C07C2603/02; C07C2603/40; C07C2603/42; C07C2603/44; C07C2603/46
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
61 words
A METHOD FOR THE HYDROGENOLYSIS OF CHLORETETRACYCLINE TO TETRACYCLINE WHICH COMPRISES REDUCING WITH HYDROGEN AT A TEMPERATURE IN THE RANGE OF O* C. TO 100* C. A SOLUTION OF CHLORTETRACYCLINE IN A SOLVENT THEREFOR AND HAVING SUSPENDED THEREIN ABOUT 5% TO 20% ON THE WEIGHT OF SAID CHLORTETRACYCLINE OF A CATALYST COMPRISING PALLADIUM HYDROXIDE DISTRIBUTED ON A FINELY DIVIDED POROUS CARRIER.
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) | 1959-01-16 | 1959-07-18 | 1960-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-01-16 | 1963-07-18 | 1964-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-01-16 | 1967-07-18 | 1968-01-17 | $7700.00 | Window Closed / Lapsed |