US3657227A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing pregnanes
Assignee: F Hoffmann La Roche AG
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Filing: 1969-12-11
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Granted: 1972-04-18
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Expires: 1989-12-11
Abstract
Abstract A PROCESS FOR PRODUCING 4,6-DIHALO-16-ALKYLIDENE PREGNA-4,6-DIENE-3,20-DIONES USEFUL AS PROGESTATIONAL AGENTS FROM A 16A,17A-EPOXY-3-ALKANOYLOXY-16-ALKYL-PREGN-5-EN20-ONE, AND INTERMEDIATES THEREOF.
Inventors
- 👤 Richard Wightman Kierstead
- 👤 Perry Rosen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:27
CPC Classifications
C; C07; C07J; C07J7/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |