Patent US2749356A successfully refreshed from Google Patents.
US2749356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of isolating and purifying keto steroids and new keto steroid compounds
Assignee: Laboratoires Francais de Chimiotherapie SA
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Filing: 1953-02-12
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Granted: 1956-06-05
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Expires: 1973-02-12
Abstract
No abstract record available.
Inventors
- 👤 Vellnz Leon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:31
CPC Classifications
C; C07; C07J; C07J75/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
95 words
IN A METHOD OF PURIFYING AND SELECTIVELY ISOLATING ESTRONE FROM A MIXTURE CONTAINING ESTRONE AND EQUILINE AND EQUILENINE, THE STEPS COMPRISING DISSOLVING SAID MIXTURE IN METHANOL CONTAINING ACETIC ACID, ADDING THERETO THE HYDRAZIDE OF BENZILIC ACID, BOILING SAID REACTION MIXTURE UNDER REFLUX TO CONDENSE SAID HYDRAZIDE WITH THE KETO STEROIDS PRESENT IN SAID MIXTURE, COOLING SAID REACTION MIXTURE, SEPARATING THE SELECTIVELY PRECIPITATED BENZILIC ACID HYDRAZONE OF ESTRONE, HEATING SAID HYDRAZONE IN SOLUTION IN AN ORGANIC SOLVENT WITH HYDROCHLORIC ACID TO SPLIT UP SAID HYDRAZONE, COOLING THE CLEAVAGE SOLUTION, AND SEPARATING THE PURE ESTRONE REGENERATED THEREBY.
Claim 2
Dependent Claim
95 words
IN A METHOD OF PURIFYING AND SELECTIVELY ISOLATING ESTRONE FROM A MIXTURE CONTAINING ESTRONE AND EQUILINE AND EQUILENINE, THE STEPS COMPRISING DISSOLVING SAID MIXTURE IN METHANOL CONTAINING ACETIC ACID, ADDING THERETO THE HYDRAZIDE OF BENZILIC ACID, BOILING SAID REACTION MIXTURE UNDER REFLUX TO CONDENSE SAID HYDRAZIDE WITH THE KETO STEROIDS PRESENT IN SAID MIXTURE, COOLING SAID REACTION MIXTURE, SEPARATING THE SELECTIVELY PRECIPITATED BENZILIC ACID HYDRAZONE OF ESTRONE, HEATING SAID HYDRAZONE IN SOLUTION IN AN ORGANIC SOLVENT WITH HYDROCHLORIC ACID TO SPLIT UP SAID HYDRAZONE, COOLING THE CLEAVAGE SOLUTION, AND SEPARATING THE PURE ESTRONE REGENERATED THEREBY.
References Cited (Backward Citations)
US2103735A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-06-05 | 1959-12-05 | 1960-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-06-05 | 1963-12-05 | 1964-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-06-05 | 1967-12-05 | 1968-06-05 | $7700.00 | Window Closed / Lapsed |