US2655535A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of chlortetracycline
Assignee: Wyeth Holdings LLC
•
Filing: 1949-11-23
•
Granted: 1953-10-13
•
Expires: 1969-11-23
Abstract
No abstract record available.
Inventors
- 👤 Pidacks Charles
- 👤 Edward E Starbird
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:02
CPC Classifications
C; C07; C07C; C07C233/00; C07C237/00; C07C237/24; C07C237/26; Y; Y10; Y10S; Y10S435/00; Y10S435/814; Y10S435/816
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
118 words
IN THE PROCESS OF RECOVERING CHLORTETRACYCLINE, THE STEPS WHIC COMPRISES EXTRACTAING AN ACIDIC AQUEOUS CHLORTETRACYCLINE CONTAINING LIQUID WITH A VOLATILE INORGANIC-SALT-SOLUTION IMMISCIBLE SOLVENT SELECTED FROM THE GROUP CONSISTING OF LOWER ALIPHATIC ALCOHOLS, BENZYL ALCOHOL, ACETONE AND LOWER ALKYL ESTERS OF THE LOWER FATTY ACIDS IN THE PRESENCE OF A WATER-SOLUBLE INORGANIC SALT SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL, ALKALINE EARTH METAL, AMMONIUM AND LOWER ALKYL AMINE, HALIDES AND SULFATES, SAID SOLVENT BEING PRESENT IN AT LEAST SUCH QUANTITY THAT AN AMOUNT OF PURE CHLORTETRACYCLINE EQUAL TO THE AMOUNT CHLORTETRACYCLINE CONTENT OF SAID CHLORTETRACYCLINE-CONTAINING LIQUOR IS SOLUBLE IN SAID SOLVENT, SEPARATING THE SOLVENT EXTRACT FROM THE RESUDUAL AQUEOUS LIQUID AND RECOVERING THE CHLORTETRACYCLINE FROM SAID SOLVENT EXTRACT.
Claim 2
Dependent Claim
118 words
IN THE PROCESS OF RECOVERING CHLORTETRACYCLINE, THE STEPS WHIC COMPRISES EXTRACTAING AN ACIDIC AQUEOUS CHLORTETRACYCLINE CONTAINING LIQUID WITH A VOLATILE INORGANIC-SALT-SOLUTION IMMISCIBLE SOLVENT SELECTED FROM THE GROUP CONSISTING OF LOWER ALIPHATIC ALCOHOLS, BENZYL ALCOHOL, ACETONE AND LOWER ALKYL ESTERS OF THE LOWER FATTY ACIDS IN THE PRESENCE OF A WATER-SOLUBLE INORGANIC SALT SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL, ALKALINE EARTH METAL, AMMONIUM AND LOWER ALKYL AMINE, HALIDES AND SULFATES, SAID SOLVENT BEING PRESENT IN AT LEAST SUCH QUANTITY THAT AN AMOUNT OF PURE CHLORTETRACYCLINE EQUAL TO THE AMOUNT CHLORTETRACYCLINE CONTENT OF SAID CHLORTETRACYCLINE-CONTAINING LIQUOR IS SOLUBLE IN SAID SOLVENT, SEPARATING THE SOLVENT EXTRACT FROM THE RESUDUAL AQUEOUS LIQUID AND RECOVERING THE CHLORTETRACYCLINE FROM SAID SOLVENT EXTRACT.
References Cited (Backward Citations)
US2482055A
Cited
US2481763A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-10-12 | 1957-04-13 | 1957-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-10-12 | 1961-04-13 | 1961-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-10-12 | 1965-04-13 | 1965-10-13 | $7700.00 | Window Closed / Lapsed |