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US2851456A
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Process for the preparation of 11alpha-hydroxy diosgenin and 11alpha-hydroxy yamogenin
Assignee: Individual
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Filing: 1957-10-22
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Granted: 1958-09-09
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Expires: 1977-10-22
Abstract
No abstract record available.
Inventors
- 👤 Edward S Rothman
- 👤 Monroe E Wall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:16
CPC Classifications
C; C07; C07J; C07J71/00; C07J75/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
82 words
A PROCESS FOR THE PREPARATION OF 11A - HYDROXY DIOSGENIN FROM 3B,12B - DIACETOXY - 22A,25D - SPIROST-5EN-11-ONE, SAID PROCESS COMPRISING REDUCING 3B,12B-DIACETOXY - 22A,25D - SPIROST - 5 - EN - 11 - ONE IN A SYSTEM COMPRISING A SOLUTION OF A METAL SELECTED FROM THE GROUP CONSISTING OF ALKALI METALS AND ALKALINE EARTH METALS IN LIQUID AMMONIA TO WHICH A WEAK PROTON DONATING SOLVENT SELECTED FROM THE GROUP CONSISTING OF WATER, ACETONE, AND LOW MOLECULAR WEIGHT ALCOHOLS HAS BEEN ADDED.
Claim 2
Dependent Claim
82 words
A PROCESS FOR THE PREPARATION OF 11A - HYDROXY DIOSGENIN FROM 3B,12B - DIACETOXY - 22A,25D - SPIROST-5EN-11-ONE, SAID PROCESS COMPRISING REDUCING 3B,12B-DIACETOXY - 22A,25D - SPIROST - 5 - EN - 11 - ONE IN A SYSTEM COMPRISING A SOLUTION OF A METAL SELECTED FROM THE GROUP CONSISTING OF ALKALI METALS AND ALKALINE EARTH METALS IN LIQUID AMMONIA TO WHICH A WEAK PROTON DONATING SOLVENT SELECTED FROM THE GROUP CONSISTING OF WATER, ACETONE, AND LOW MOLECULAR WEIGHT ALCOHOLS HAS BEEN ADDED.
References Cited (Backward Citations)
US2776969A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-09-08 | 1962-03-10 | 1962-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-08 | 1966-03-10 | 1966-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-08 | 1970-03-10 | 1970-09-09 | $7700.00 | Window Closed / Lapsed |