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US4888423A
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6-(4-Hydroxyphenyl)-4,5-dihydro-3(2h)-pyridazinones and stabilized compositions
Assignee: Novartis Corp
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Filing: 1986-10-06
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Granted: 1989-12-19
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Expires: 2006-10-06
Abstract
Abstract 6-(4-hydroxyphenyl)-4,5-dihydro-3(2H)-pyridazinones of formula I <IMAGE> (I) where R1 and R2 are independently alkyl, cycloalkyl, aryl or aralkyl, R3 and R4 are independently hydrogen or alkyl, n is 1 to 4 and T is hydrogen, alkyl, substituted alkyl, alkylene or arylene, are effective in stabilizing organic materials against oxidative, thermal and actinic degradation.
Inventors
- 👤 Paul A. Odorisio
- 👤 Steven D. Pastor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:08
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/16; C08K5/34; C08K5/3442; C08K5/3462; C07; C07D; C07D237/00; C07D237/02; C07D237/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
42 words
A compound of formula Ia or Ib ##STR4## wherein R 1 and R 2 are each tert-butyl, R 3 and R 4 are each hydrogen, T is hydrogen, phenyl, 2-hydroxyethyl or 2-bromoethyl, and E is alkylene of 4 to 8 carbon atoms.
Claim 2
Dependent Claim
42 words
A compound of formula Ia or Ib ##STR4## wherein R 1 and R 2 are each tert-butyl, R 3 and R 4 are each hydrogen, T is hydrogen, phenyl, 2-hydroxyethyl or 2-bromoethyl, and E is alkylene of 4 to 8 carbon atoms.
Claim 3
Dependent Claim
10 words
The compound according to claim 1 which is bis-2,2'[6-(3,5-di-tert-butyl-4hydroxyphenyl)-4,5-dihydro-3(2H)-pyridazin-2-yl[-ethyl adipate.
Claim 4
Dependent Claim
9 words
The compound according to claim 1 which is 2-(2-bromoethyl)-6-(3,5-di-tert-butyl-4-hydroxyphenyl)-4,5-di-hydro-3(2H)-pyridazinone.
Claim 5
Dependent Claim
9 words
The compound according to claim 1 which is 6-(3,5-di-tert-butyl-4-hydroxyphenyl)-4,5-dihydro-3(2H)-pyridazinone.
Claim 6
Dependent Claim
9 words
The compound according to claim 1 which is 6-(3,5-di-tert-butyl-4-hydroxyphenyl)-4,5-dihydro-2-phenyl-3(2H)-pyridazinone.
Claim 7
Dependent Claim
9 words
The compound according to claim 1 which is 6-(3,5-di-tert-butyl-4-hydroxyphenyl)-4,5-dihydro-2-(2-hydroxyethyl)-3(2H)-pyridazinone.
Claim 8
Dependent Claim
10 words
The compound according to claim 1 which is bis-2,2'-[6-(3,5-di-tert-butyl-4-hydroxyphenyl)-4,5-di-hydro-3(2H)-pyridazin-2-yl]ethyl sebacate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-18 | 1993-06-19 | 1993-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-18 | 1997-06-19 | 1997-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-18 | 2001-06-19 | 2001-12-19 | $7700.00 | Window Closed / Lapsed |