Patent US3899493A successfully refreshed from Google Patents.
US3899493A
Expired / Lapsed
US
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Chromic acid oxidation of vinblastine sulfate to form vincristine
Assignee: Richter Gedeon Vegyeszeti Gyar Nyrt
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Filing: 1972-12-29
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Granted: 1975-08-12
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Expires: 1992-12-29
Abstract
Abstract Vincristine is prepared in a semisynthetic process starting from vinblastine. Vinblastine or a salt thereof, preferably the sulphate, is oxidized with chromic acid or with one of its salts at a low temperature, the reaction mixture is neutralized or rendered alkaline and the product is separated therefrom by extraction, the extract is evaporated to dryness, the dry residue is optionally formylated, vincristine, and optionally Ndemethylvinblastine too, are isolated from the product, and the product(s) are optionally converted into their salts, preferably into the sulphates.
Inventors
- 👤 Karolina Jovanovics
- 👤 Kalman Szasz
- 👤 Gyorgy Fekete
- 👤 Emil Bittner
- 👤 Eszter Dezseri
- 👤 Janos Eles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:13
CPC Classifications
C; C07; C07D; C07D519/00; C07D519/04
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
60 words
A PROCESS FOR THE PREPARATION OF VINCRISTINE, COMPRISING THE SYEPS OF OXIDIZING THE SULFATE SALT OF VINBLASTINE WITH CHROMIC ACID IN AN ORGANIC SOLVENT SELECTED FROM THE GROUP CONSISTING OF ACETIC ACID AND MIXTURES OF GLACIAL ACETIC ACID AND ACETONE AT A TEMPERATURE OF ABOUT -60*C , ADJUSTING THE REACTION MIXTURE TO A PH OF 7-9 AND RECOVERING THE VINCRISTINE
Claim 2
Dependent Claim
60 words
A PROCESS FOR THE PREPARATION OF VINCRISTINE, COMPRISING THE SYEPS OF OXIDIZING THE SULFATE SALT OF VINBLASTINE WITH CHROMIC ACID IN AN ORGANIC SOLVENT SELECTED FROM THE GROUP CONSISTING OF ACETIC ACID AND MIXTURES OF GLACIAL ACETIC ACID AND ACETONE AT A TEMPERATURE OF ABOUT -60*C , ADJUSTING THE REACTION MIXTURE TO A PH OF 7-9 AND RECOVERING THE VINCRISTINE
Claim 3
Dependent Claim
21 words
A process according to claim 1, wherein said mixture of glacial acetic acid and acetone is in a ratio of 4:1.
Claim 4
Dependent Claim
29 words
A process according to claim 1, wherein after the oxidation step, the pH is adjusted to 7-9 with concentrated ammonium hydroxide solution at a temperature no greater than 50*C.
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) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |