Patent US2555760A successfully refreshed from Google Patents.
US2555760A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of streptomycin from orange ii salt
Assignee: Pfizer Inc
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Filing: 1947-05-06
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Granted: 1951-06-05
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Expires: 1967-05-06
Abstract
No abstract record available.
Inventors
- 👤 Peter P Regna
- 👤 Isaiah A Solomons
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:22
CPC Classifications
C; C07; C07H; C07H15/00; C07H15/20; C07H15/22; C07H15/238
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
91 words
A PROCESS WHICH COMPRISES SUSPENDING A STREPTOMYCIN SALT OF P-(2-HYDROXY-1-NAPHTHYLAZO)-BENZENE SULFONIC ACID IN A SOLVENT WHICH IS CAPABLE OF DISSOLVING STREPTOMCYIN HYDROCHLORIDE, ADDING A SOLUTION OF BARIUM CHLORIDE IN SAID SOLVENT IN EXVESS OF THE AMOUNT REQUIRED TO PRECIPITATE ALL OF THE P-(2-HYDROXY-1-NAPHTHYLAZO)BENZENE SULFONIC ACID AS AN INSOLUTION BARIUM SALT OF P-(2-HYDROXY-1-NAPHTHYLAZO) BENZENE SULFONIC ACID AND TO FORM A SOLUTION OF STREPTOMYCIN HYDROCHLORIDE, REMOVING THE EXCESS OF SAID BARIUM CHLORIDE REMAINING IN THE SOLUTION OF THE STREPTOMYCIN HYDROCHLORIDE AND ISOLATING THE STREPTOMYCIN AS A METAL-FREE, WATER-SOLUBLE SALT OF HIGH ANTIBIOTIC POTENCY.
Claim 2
Dependent Claim
91 words
A PROCESS WHICH COMPRISES SUSPENDING A STREPTOMYCIN SALT OF P-(2-HYDROXY-1-NAPHTHYLAZO)-BENZENE SULFONIC ACID IN A SOLVENT WHICH IS CAPABLE OF DISSOLVING STREPTOMCYIN HYDROCHLORIDE, ADDING A SOLUTION OF BARIUM CHLORIDE IN SAID SOLVENT IN EXVESS OF THE AMOUNT REQUIRED TO PRECIPITATE ALL OF THE P-(2-HYDROXY-1-NAPHTHYLAZO)BENZENE SULFONIC ACID AS AN INSOLUTION BARIUM SALT OF P-(2-HYDROXY-1-NAPHTHYLAZO) BENZENE SULFONIC ACID AND TO FORM A SOLUTION OF STREPTOMYCIN HYDROCHLORIDE, REMOVING THE EXCESS OF SAID BARIUM CHLORIDE REMAINING IN THE SOLUTION OF THE STREPTOMYCIN HYDROCHLORIDE AND ISOLATING THE STREPTOMYCIN AS A METAL-FREE, WATER-SOLUBLE SALT OF HIGH ANTIBIOTIC POTENCY.
References Cited (Backward Citations)
US2462175A
Cited
US2446102A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-06-04 | 1954-12-04 | 1955-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-06-04 | 1958-12-04 | 1959-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-06-04 | 1962-12-04 | 1963-06-05 | $7700.00 | Window Closed / Lapsed |