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US3676436A
Expired / Lapsed
US
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Novel aminophenyl alkoxy coumarins
Assignee: Pharmacia and Upjohn Co
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Filing: 1970-03-16
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Granted: 1972-07-11
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Expires: 1990-03-16
Abstract
Abstract Alkoxy - substituted 3-(aminophenyl)-coumarins are prepared by hydrogenation of the corresponding nitrophenylcoumarin derivative in the presence of Raney nickel or a noble metal catalyst. The novel amino compounds are useful, by virtue of fluorescence in ultraviolet light, as optical brighteners, as ultraviolet light filters, in the preparation of polyureas and photoresist polymers. Also, the novel amino compounds can be phosgenated to yield the corresponding isocyanates.
Inventors
- 👤 Durvasula V Rao
- 👤 Adnan A R Sayigh
- 👤 Henri Ulrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:39
CPC Classifications
C; C07; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/06; C07D311/08; C07D311/12; C07D311/14; C07D311/16
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
1 words
3-(4''-aminophenyl)-6-methoxycoumarin.
References Cited (Backward Citations)
US3074963A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |