US3763232A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alpha-aminoalkyl-4-hydroxy-3-ureidobenzyl alcohols
Assignee: Smith Kline & French Laboratories Ltd
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Filing: 1971-01-11
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Granted: 1973-10-02
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Expires: 1991-01-11
Abstract
Abstract A-AMINOALKYL-4-HYDROXY-3-UREIDOBENZYL ALCOHOLS HAVING B-ADRENERGIC STIMULANT ACTIVITY, PARTICULARLY AS SELECTIVE BRONCHODILATORS, ARE PREPARED GENERALLY FROM 3AMINO-4-BENZYLOXYPHENONES BY, FOR EXAMPLE, CONVERSION TO AN ISOCYANATE, REACTION WITH AMMONIA OR A MONOSUBSTITUTED ALKYL OR ARYL AMINE TO GIVE 3-UREIDOPHENONES, BROMINATION OF THESE PHENONES AND TREATMENT OF THE RESULTING A-BROMO DERIVATIVES WITH AN N-BENZYL SECONDARY AMINE, FOLLOWED BY CATALYTIC HYDROGENATION TO REMOVE THE BENZYL GROUPS AND REDUCE THE KETONE MOIETY.
Inventors
- 👤 C Kaiser
- 👤 S Ross
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:48
CPC Classifications
C; C07; C07C; C07C265/00; C07C265/12; C07C275/00; C07C275/28; C07C275/32; C07C275/34; C07C275/38
Claims Analysis
Total Claims: 0
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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) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |