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US3822254A
Expired / Lapsed
US
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Synthesis of 25-hydroxycholesterol
Assignee: F Hoffmann La Roche AG
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Filing: 1973-05-21
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Granted: 1974-07-02
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Expires: 1993-05-21
Abstract
Abstract 25-HYDROXYCHOLESTEROL, AN INTERMEDIATE IN THE PREPARATION OF BIOLOGICALLY IMPORTANT METABOLITES OF VITAMIN D3 IS SYNTHESIZED IN A MULTI-STEP PROCESS FROM STIGMASTEROL.
Inventors
- 👤 J Partridge
- 👤 M Uskokovic
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:42
CPC Classifications
C; C07; C07J; C07J53/00; A; A61; A61P; A61P29/00; A61P3/00; A61P3/02
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) | 1977-07-01 | 1977-12-31 | 1978-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-01 | 1981-12-31 | 1982-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-01 | 1985-12-31 | 1986-07-02 | $7700.00 | Window Closed / Lapsed |