Patent US2649480A successfully refreshed from Google Patents.
US2649480A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of oxytetracycline
Assignee: Pfizer Inc
•
Filing: 1950-04-03
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Granted: 1953-08-18
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Expires: 1970-04-03
Abstract
No abstract record available.
Inventors
- 👤 Peter P Regna
- 👤 Rudolph A Carboni
- 👤 Albert E Timreck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 01:04
CPC Classifications
C; C07; C07C; C07C233/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
42 words
IN THE RECOVERY OF OXYTETRACYCLINE FROM A DILUTE AQUEOUS SOLUTION THEREOF DERIVED FROM A MICROORGANISM FERMENTATION BROTH, THE STEP OF ADDING TO SUCH A SOLUTION MAINTAINED AT A PH OF FROM ABOUT 1.5 TO ABOUT 3.5 AND ARYL AZO SULFONIC ACID DYE.
Claim 2
Dependent Claim
42 words
IN THE RECOVERY OF OXYTETRACYCLINE FROM A DILUTE AQUEOUS SOLUTION THEREOF DERIVED FROM A MICROORGANISM FERMENTATION BROTH, THE STEP OF ADDING TO SUCH A SOLUTION MAINTAINED AT A PH OF FROM ABOUT 1.5 TO ABOUT 3.5 AND ARYL AZO SULFONIC ACID DYE.
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) | 1956-08-17 | 1957-02-16 | 1957-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-08-17 | 1961-02-16 | 1961-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-08-17 | 1965-02-16 | 1965-08-18 | $7700.00 | Window Closed / Lapsed |