US2974167A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Active derivatives of the tetracycline antibiotics
Assignee: Pfizer Inc
•
Filing: 1958-02-26
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Granted: 1961-03-07
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Expires: 1978-02-26
Abstract
No abstract record available.
Inventors
- 👤 Jr Charles R Stephens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:34
CPC Classifications
C; C07; C07C; C07C233/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
124 words
THE PROCESS WHICH COMPRISES REACTING IN A SUBSTANTIALLY NON-AQUEOUS INERT SOLVENT A TETRACYCLINE ANTIBIOTIC SELECTED FROM THE GROUP CONSISTING OF TETRACYCLINE, OXYTETRACYCLINE, CHLORETETRACYCLINE, THE MINERAL ACID ADDITION SALTS THEREOF, THE P-TOLUENESULFONIC SALTS THEREOF, THE ALKALI METAL SALTS THEREOF, THE CALCUM SALTS THEREOF, AND THE BARIUM SALTS THEREOF WITH AT LEAST ONE MOLECULAR PROPORTION OF A CARBONYL COMPOUND TO OBTAIN THE 1:1 ADDUCT OF SAID TETRACYCLINE ANTIBIOTIC AND SAID CARBONYL COMPOUND, SAID CARBONYL COMPOUND BEING SELECTED FROM THE GROUP CONSISTING OF CHORAL, GLYOXAL, BROMAL, 1,2,3-INDANETRIONE, DIACETYL, ACETYL CYANIDE, ETHYL PYRUVATE, PYRUVALDEHYDE, BENZOYL CYANIDE, PHENYLGLYOXAL, ETHYL PHENYLPYRUVATE, DIETHYL OXALOCETATE, ETHYL 4-NITROPHENYLPYRUVATE, 5-NITROFURFURAL, AND 2-METHYL-3-FORMYQUINOXALINE-1,4-DIOXIDE, THE TEMPERATURE OF REACTION BEING FROM ABOUT 15* TO ABOUT 85*C. AND THE TIME OF REACTION BEING UP TO ABOUT 100 HOURS.
Claim 2
Dependent Claim
124 words
THE PROCESS WHICH COMPRISES REACTING IN A SUBSTANTIALLY NON-AQUEOUS INERT SOLVENT A TETRACYCLINE ANTIBIOTIC SELECTED FROM THE GROUP CONSISTING OF TETRACYCLINE, OXYTETRACYCLINE, CHLORETETRACYCLINE, THE MINERAL ACID ADDITION SALTS THEREOF, THE P-TOLUENESULFONIC SALTS THEREOF, THE ALKALI METAL SALTS THEREOF, THE CALCUM SALTS THEREOF, AND THE BARIUM SALTS THEREOF WITH AT LEAST ONE MOLECULAR PROPORTION OF A CARBONYL COMPOUND TO OBTAIN THE 1:1 ADDUCT OF SAID TETRACYCLINE ANTIBIOTIC AND SAID CARBONYL COMPOUND, SAID CARBONYL COMPOUND BEING SELECTED FROM THE GROUP CONSISTING OF CHORAL, GLYOXAL, BROMAL, 1,2,3-INDANETRIONE, DIACETYL, ACETYL CYANIDE, ETHYL PYRUVATE, PYRUVALDEHYDE, BENZOYL CYANIDE, PHENYLGLYOXAL, ETHYL PHENYLPYRUVATE, DIETHYL OXALOCETATE, ETHYL 4-NITROPHENYLPYRUVATE, 5-NITROFURFURAL, AND 2-METHYL-3-FORMYQUINOXALINE-1,4-DIOXIDE, THE TEMPERATURE OF REACTION BEING FROM ABOUT 15* TO ABOUT 85*C. AND THE TIME OF REACTION BEING UP TO ABOUT 100 HOURS.
References Cited (Backward Citations)
US2736735A
Cited
US2734018A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-03-06 | 1964-09-05 | 1965-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-03-06 | 1968-09-05 | 1969-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-03-06 | 1972-09-05 | 1973-03-07 | $7700.00 | Window Closed / Lapsed |