US4066655A
Expired / Lapsed
US
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4,10-Dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acids, salts and esters
Assignee: Warner Lambert Co LLC
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Filing: 1976-10-29
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Granted: 1978-01-03
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Expires: 1996-10-29
Abstract
Abstract The present invention relates to 4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acids, salts and esters having the formula: ##STR1## wherein R 1 is hydrogen, lower alkyl, halogen, hydroxy or lower alkoxy; R 2 is hydrogen, aralkyl or lower alkyl; R 3 is hydrogen or lower alkyl and their pharmaceutically acceptable salts. These compounds are indicated in the management of allergic conditions such as bronchial asthma, hay fever and the like.
Inventors
- 👤 David T. Connor
- 👤 Patricia A. Young
- 👤 Max VON Strandtmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:16
CPC Classifications
C; C07; C07D; C07D491/00; C07D491/02; C07D491/04; C07D311/00; C07D311/02; C07D311/04; C07D311/22
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
40 words
A compound of the formula: ##STR23## wherein R 1 is hydrogen, lower alkyl, halogen, hydroxy or lower alkoxy; R 2 is hydrogen phenyl lower alkyl or lower alkyl; R 3 is hydrogen or lower alkyl and their pharmaceutically acceptable salts.
Claim 2
Dependent Claim
40 words
A compound of the formula: ##STR23## wherein R 1 is hydrogen, lower alkyl, halogen, hydroxy or lower alkoxy; R 2 is hydrogen phenyl lower alkyl or lower alkyl; R 3 is hydrogen or lower alkyl and their pharmaceutically acceptable salts.
Claim 3
Dependent Claim
10 words
A compound according to claim 1 which is ethyl 8-chloro-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylate.
Claim 4
Dependent Claim
10 words
A compound according to claim 1 which is ethyl 4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylate.
Claim 5
Dependent Claim
10 words
A compound according to claim 1 which is ethyl 7-methoxy-4,10-dihydro-4.10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylate.
Claim 6
Dependent Claim
10 words
A compound according to claim 1 which is ethyl 1-methyl-8-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylate.
Claim 7
Dependent Claim
10 words
A compound according to claim 1 which is ethyl 1-methyl-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylate.
Claim 8
Dependent Claim
10 words
A compound according to claim 1 which is ethyl 1-ethyl-8-chloro-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylate.
Claim 9
Dependent Claim
10 words
A compound according to claim 1 which is ethyl 1-butyl-8-chloro-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylate.
Claim 10
Dependent Claim
10 words
A compound according to claim 1 which is 8-chloro-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acid.
Claim 11
Dependent Claim
10 words
A compound according to claim 1 which is 4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acid.
Claim 12
Dependent Claim
10 words
A compound according to claim 1 which is 7-methoxy-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acid.
Claim 13
Dependent Claim
10 words
A compound according to claim 1 which is 1-methyl-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acid.
Claim 14
Dependent Claim
10 words
A compound according to claim 1 which is 1-methyl-8-chloro-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acid.
Claim 15
Dependent Claim
10 words
A compound according to claim 1 which is 1-ethyl-8-chloro-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acid.
Claim 16
Dependent Claim
10 words
A compound according to claim 1 which is 1-butyl-8-chloro-4,10-dihydro-4,10-dioxo-1H-1-benzopyrano[3,2-b]pyridine-3-carboxylic acid.
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) | 1981-01-02 | 1981-07-04 | 1982-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-02 | 1985-07-04 | 1986-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-02 | 1989-07-04 | 1990-01-03 | $7700.00 | Window Closed / Lapsed |