Patent US2644816A successfully refreshed from Google Patents.
US2644816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of antibiotics with water insoluble carboxylic acids
Assignee: Mathieson Chemical Corp
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Filing: 1947-07-19
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Granted: 1953-07-07
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Expires: 1967-07-19
Abstract
No abstract record available.
Inventors
- 👤 William A Lott
- 👤 Braker William
- 👤 O'keeffe Andrew Ellis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:42
CPC Classifications
C; C07; C07H; C07H15/00; C07H15/20; C07H15/22; C07H15/238
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
41 words
THE METHOD WHICH COMPRISES INTIMATELY CONTACTING AN AQUEOUS SOLUTION OF AN ANTIBIOTIC OF THE GROUP CONSISTING OF STREPTOMYCIN, DIHYDROSTREPTOMYCIN, STREPTOTHRICIN, AND WATER-SOLUBLE SALTS OF THESE WITH A SUBSTANTIALLY WATERINSOLUBLE CARBOXYLIC ACID AND A SUBSTANTIALLY WATER-IMMISCIBLE ORGANIC SOLVENT FOR THE CARBOXYLIC ACID.
Claim 2
Independent Claim
41 words
THE METHOD WHICH COMPRISES INTIMATELY CONTACTING AN AQUEOUS SOLUTION OF AN ANTIBIOTIC OF THE GROUP CONSISTING OF STREPTOMYCIN, DIHYDROSTREPTOMYCIN, STREPTOTHRICIN, AND WATER-SOLUBLE SALTS OF THESE WITH A SUBSTANTIALLY WATERINSOLUBLE CARBOXYLIC ACID AND A SUBSTANTIALLY WATER-IMMISCIBLE ORGANIC SOLVENT FOR THE CARBOXYLIC ACID.
Claim 3
Independent Claim
70 words
THE METHOD OF PURIFYING STREPTOMYCIN, WHICH COMPRISES TREATING A PRIMARY STREPTOMYCIN-CONTAINING LIQUID WITH AN ACTIVATED CHARCOAL, ELUTING THE STREPTOMYCIN FROM THE CHARCOAL WITH AN AQUEOUS, WATER-SOLUBLE MINERAL ACID, INTIMATELY CONTACTING THE ELUATE WITH A SUBSTANTIALLY WATER-INSOLUBLE CARBOXYLIC ACID AND A SUBSTANTIALLY WATER-IMMISCIBLE ORGANIC SOLVENT FOR THE CARBOXYLIC ACID, RECOVERING THE ORGANIC SOLVENT PHASE, INTIMATELY CONTACTING THE ORGANIC SOLVENT SOLUTION WITH AN AQUEOUS, WATER-SOLUBLE, RELATIVELY-STRONG ACID, AND RECOVERING THE AQUEOUS PHASE.
Claim 4
Independent Claim
70 words
THE METHOD OF PURIFYING STREPTOMYCIN, WHICH COMPRISES TREATING A PRIMARY STREPTOMYCIN-CONTAINING LIQUID WITH AN ACTIVATED CHARCOAL, ELUTING THE STREPTOMYCIN FROM THE CHARCOAL WITH AN AQUEOUS, WATER-SOLUBLE MINERAL ACID, INTIMATELY CONTACTING THE ELUATE WITH A SUBSTANTIALLY WATER-INSOLUBLE CARBOXYLIC ACID AND A SUBSTANTIALLY WATER-IMMISCIBLE ORGANIC SOLVENT FOR THE CARBOXYLIC ACID, RECOVERING THE ORGANIC SOLVENT PHASE, INTIMATELY CONTACTING THE ORGANIC SOLVENT SOLUTION WITH AN AQUEOUS, WATER-SOLUBLE, RELATIVELY-STRONG ACID, AND RECOVERING THE AQUEOUS PHASE.
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) | 1956-07-06 | 1957-01-05 | 1957-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-06 | 1961-01-05 | 1961-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-06 | 1965-01-05 | 1965-07-07 | $7700.00 | Window Closed / Lapsed |