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US4264602A
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4-Hydroxy-3-nitro-pyrido[2,3-B]pyridine-2(1H)-ones
Assignee: Sandoz Inc
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Filing: 1976-07-21
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Granted: 1981-04-28
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Expires: 1996-07-21
Abstract
Abstract Anti-allergic 4-hydroxy-3-nitro-pyrido[2,3-b]pyridines-2(1H)-ones are prepared by reacting a 3,4-dihydro-1,3-dioxo-1H-pyrido[2,3-d][1,3]oxazine (a 3-azaisatoic anhydride) with the carbanion resulting from the reaction of nitro acetic acid alkyl esters with a proton abstracting agent.
Inventors
- 👤 Goetz E. Hardtmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:41
CPC Classifications
C; C07; C07D; C07D471/00; C07D471/02; C07D471/04
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
33 words
A compound of the formula: ##STR6## wherein R o is alkyl of 1 to 6 carbon atoms or allyl, M is hydrogen or a pharmaceutically acceptable cation, and R' is hydrogen or methyl.
Claim 2
Dependent Claim
33 words
A compound of the formula: ##STR6## wherein R o is alkyl of 1 to 6 carbon atoms or allyl, M is hydrogen or a pharmaceutically acceptable cation, and R' is hydrogen or methyl.
Claim 3
Dependent Claim
10 words
A compound of claim 1 in which M is hydrogen.
Claim 4
Dependent Claim
10 words
A compound of claim 1 in which R' is hydrogen.
Claim 5
Dependent Claim
8 words
The compound of claim 1 which is 1,7-dimethyl-4-hydroxy-3-nitro-pyrido[2,3-b]pyridine-2(1H)-one.
Claim 6
Dependent Claim
8 words
The compound of claim 1 which is 1-allyl-7-methyl-4-hydroxy-3-nitro-pyrido[2,3-b]pyridine-2(1H)-one.
Claim 7
Dependent Claim
22 words
A pharmaceutical composition comprising an inert pharmaceutically acceptable carrier and a symptomatic allergy treating effective amount of a compound of claim 1.
Claim 8
Dependent Claim
32 words
The method of symptomatically treating allergic conditions due to histamine release comprising administering to a mammal in need of such treatment an allergy treating effective amount of a compound of claim 1.
Claim 9
Dependent Claim
10 words
The method of claim 7 in which R' is hydrogen.
Claim 10
Dependent Claim
11 words
The method of claim 7 in which the compound is 1,7-dimethyl-4-hydroxy-3-nitro-pyrido[2,3-b]pyridine-2(1H)-one.
Claim 11
Dependent Claim
11 words
The method of claim 7 in which the compound is 1-allyl-7-methyl-4-hydroxy-3-nitro-pyrido[2,3-b]pyridine-2(1H)-one.
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) | 1984-04-27 | 1984-10-27 | 1985-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-27 | 1988-10-27 | 1989-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-27 | 1992-10-27 | 1993-04-28 | $7700.00 | Window Closed / Lapsed |