US3553223A
Expired / Lapsed
US
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Acid catalyzed cyclization of tetrahydropyridines containing an electron withdrawing group on the nitrogen
Assignee: F Hoffmann La Roche AG
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Filing: 1968-01-05
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Granted: 1971-01-05
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Expires: 1988-01-05
Abstract
Abstract THERE IS DESCRIBED A PROCESS FOR THE ACID CATALYZED CYCLIZATION OF 2- (4-METHOXYBENZYL)-3,4-DIALKYL-1,2,5,6TETRAHYDROPYRIDINES SUBSTITUTED AT THE NITROGEN ATOM WITH ELECTRON WITHDRAWING GROUPS, TO THE CORRESPONDING BENZOMORPHAN COMPOUNDS UTILIZING NOVEL INTERMEDIATES. THE BENZOMORPHAN COMPOUNDS SO PRODUCED ARE USEFUL AS INTERMEDIATES IN THE PREPARATION OF PHARMACEUTICALLY ACTIVE COMPOUNDS, E.G., KNOWN BENZOMORPHAN DERIVATIVES EXHIBITING ANALGESIC ACTIVITY.
Inventors
- 👤 Willy Leimgruber
- 👤 Ernest Mohacsi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:29
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/24; C07D213/28; C07D213/30; C07D211/00; C07D211/04; C07D211/68; C07D211/70; C07D211/80; C07D211/82; C07D221/00; C07D221/02; C07D221/22; C07D221/26
Claims Analysis
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-04 | 1974-07-06 | 1975-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-04 | 1978-07-06 | 1979-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-04 | 1982-07-06 | 1983-01-05 | $7700.00 | Window Closed / Lapsed |