Patent US3947473A successfully refreshed from Google Patents.
US3947473A
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Antioxidant chroman compounds
Assignee: Hoffmann La Roche Inc
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Filing: 1973-11-19
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Granted: 1976-03-30
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Expires: 1993-11-19
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
2026-11-05 09:02
CPC Classifications
C; C07; C07C; C07C255/00; C07C59/00; C07C59/40; C07C59/42; C07C59/52; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/58; C07D311/70; C07D311/72; C09; C09K; C09K15/00; C09K15/04; C09K15/06; C10; C10M; C10M1/00; C10M1/08; C11; C11B; C11B5/00; C11B5/0021; C11B5/0035; C10M2207/00; C10M2207/28
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
38 words
A compound of the formula: ##SPC26## wherein R 1 , R 1 ', R 1 " and R 2 are hydrogen or lower alkyl; R is hydrogen, lower alkonoyl benzyl, benzoyl; R 4 is hydrogen or lower alkyl.
Claim 2
Dependent Claim
38 words
A compound of the formula: ##SPC26## wherein R 1 , R 1 ', R 1 " and R 2 are hydrogen or lower alkyl; R is hydrogen, lower alkonoyl benzyl, benzoyl; R 4 is hydrogen or lower alkyl.
Claim 3
Dependent Claim
10 words
The compound of claim 1 wherein said compound is (±)-2-carboxy-6-hydroxy-2,5,7,8-tetramethylchroman.
Claim 4
Dependent Claim
11 words
The compound of claim 1 wherein said compound is (±)-2-ethyl-6-hydroxy-5,7,8-trimethylchroman-2-carboxylic acid.
Claim 5
Dependent Claim
11 words
The compound of claim 1 wherein said compound is (±)-6-hydroxy-5,7,8-trimethylchroman-2-carboxylic acid.
Claim 6
Dependent Claim
11 words
The compound of claim 1 wherein said compound is (±)-6-hydroxy-5,7,-diisopropyl-2-methylchroman-2-carboxylic acid.
References Cited (Backward Citations)
GB949715A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-30 | 1979-09-29 | 1980-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-30 | 1983-09-29 | 1984-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-30 | 1987-09-29 | 1988-03-30 | $7700.00 | Window Closed / Lapsed |