US4898962A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Natural vitamin E intermediate
Assignee: Hoffmann La Roche Inc
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Filing: 1989-01-30
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Granted: 1990-02-06
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Expires: 2009-01-30
Abstract
Abstract An asymmetric synthesis for Vitamin E in an optically active pure form for 4-(2,5-diloweralkanoyloxy)-3,4,6-trimethylphenyl-butan-2-one and intermediates therein.
Inventors
- 👤 Ka-Kong Chan
- 👤 Gabriel G. Saucy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:00
CPC Classifications
C; C07; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/58; C07D311/70; C07D311/72; C07C; C07C46/00; C07C46/02; C07C46/06; C07C46/10; C07C50/00; C07C50/26; C07C50/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
15 words
A compound of the formula ##STR22## wherein R 11 is mesyl, tosyl or lower alkanoyl.
Claim 2
Dependent Claim
15 words
A compound of the formula ##STR22## wherein R 11 is mesyl, tosyl or lower alkanoyl.
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) | 1993-02-05 | 1993-08-07 | 1994-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-05 | 1997-08-07 | 1998-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-05 | 2001-08-07 | 2002-02-06 | $7700.00 | Window Closed / Lapsed |