Patent US4018799A successfully refreshed from Google Patents.
US4018799A
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Antioxidant chroman compounds
Assignee: Hoffmann La Roche Inc
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Filing: 1975-12-04
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Granted: 1977-04-19
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Expires: 1995-12-04
Abstract
Abstract The (6-hydroxy-chroman-2-yl) acetic or carboxylic acid derivatives useful as antioxidants and a method for preparing these derivatives from hydroquinones and intermediates in this synthesis as well as the use of these derivatives as intermediates in the preparation of optically active alpha-tocopherol.
Inventors
- 👤 John William Scott
- 👤 David Richard Parrish
- 👤 Gabriel Saucy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:18
CPC Classifications
C; C07; C07C; C07C255/00; C11; C11B; C11B5/00; C11B5/0021; C11B5/0035
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
45 words
A compound of the formula ##STR56## wherein R 1 , R' 1 and R 1 " are hydrogen or lower alkyl; R 2 is hydrogen, lower alkyl or phenyl; R is hydrogen, lower alkanoyl, benzoyl, benzyl, benzylhydryl or tetrahydropyranyl; and R 5 is lower alkyl.
Claim 2
Dependent Claim
45 words
A compound of the formula ##STR56## wherein R 1 , R' 1 and R 1 " are hydrogen or lower alkyl; R 2 is hydrogen, lower alkyl or phenyl; R is hydrogen, lower alkanoyl, benzoyl, benzyl, benzylhydryl or tetrahydropyranyl; and R 5 is lower alkyl.
Claim 3
Dependent Claim
10 words
The compound of claim 1 wherein said compound is (±)-6-hydroxy-2-methoxy-2,5,7,8-tetramethylchroman.
Claim 4
Dependent Claim
10 words
The compound of claim 1 wherein said compound is (±)-6-acetoxy-2-methoxy-2,5,7,8-tetramethylchroman.
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) | 1980-04-18 | 1980-10-18 | 1981-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-18 | 1984-10-18 | 1985-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-18 | 1988-10-18 | 1989-04-19 | $7700.00 | Window Closed / Lapsed |