Patent US3671544A successfully refreshed from Google Patents.
US3671544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
3,4,4a,9a-tetrahydro-2-(1h)carbazolones
Assignee: Warner Lambert Co LLC
•
Filing: 1970-07-13
•
Granted: 1972-06-20
•
Expires: 1990-07-13
Abstract
Abstract The present invention discloses a new class of carbazolones having the following structural formula: These compounds are prepared in accordance with the following reaction scheme: In the above, R1 is hydrogen, lower alkyl, aryl, substituted aryl, aralkyl, lower alkoxy, aryloxy, lower alkylmercapto, arylmercapto, halo, trihaloalkyl, nitro, amino, substituted amino, acetamido, and substituted acetamido. R2, R3, R4, which can be alike or different, are hydrogen, lower alkyl, aryl, substituted aryl and aralkyl. The compounds are useful as analgesic agents.
Inventors
- 👤 Robert I Meltzer
- 👤 Raymond R Wittekind
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:57
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/56; C07D209/80; C07D209/82; C07D209/88; C07D209/02; C07D209/04; C07D209/10; C07D209/12
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
9 words
A compound according to claim 1 which is 9-Methyl-3,4,4a,9a-tetrahydro-2(1H)carbazolone.
Claim 2
Dependent Claim
9 words
A compound according to claim 1 which is 9-benzyl-3,4,4a,9a-tetrahydro-2(1H)carbazolone.
Claim 3
Dependent Claim
10 words
A compound aCcording to claim 1 which is 3,4,4a, 9a-tetrahydro-2(1H)carbazolone.
Claim 4
Dependent Claim
23 words
A process for the production of a compound according to claim 1 which comprises allowing to stand together a compound of the formula:
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) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |