Patent US4758677A successfully refreshed from Google Patents.
US4758677A
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Cyanobenzano [b] pyrans
Assignee: Beecham Group PLC
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Filing: 1982-11-17
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Granted: 1988-07-19
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Expires: 2002-11-17
Abstract
Abstract 2,2-Dimethyl-3,4-dihydro-2H-benzo[b]pyran-3-ols bearing an amino group in the 4-position and a cyano group in the benzo ring, their salts, esters and ethers, demonstrate excellent vasodilatory activity. The compounds, of which trans-2,2-dimethyl-4-isopropylamino-6-cyano-3,4-dihydro-2H-benzo[b]pyran-3-ol is a representative embodiment, can be prepared from the corresponding 3,4-epoxy derivative upon treatment with an amine.
Inventors
- 👤 John M. Evans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:00
CPC Classifications
C; C07; C07D; C07D493/00; C07D493/02; C07D493/04; C07D311/00; C07D311/02; C07D311/04; C07D311/22; C07D311/58; C07D311/68
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
1 words
2,2-dimethyl-3,4-epoxy-6-cyano-3,4-dihydro-2H-benzo[b]pyran.
Claim 2
Dependent Claim
1 words
2,2-dimethyl-3,4-epoxy-6-cyano-3,4-dihydro-2H-benzo[b]pyran.
References Cited (Backward Citations)
US4048317A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-19 | 1992-01-18 | 1992-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-19 | 1996-01-18 | 1996-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-19 | 2000-01-18 | 2000-07-19 | $7700.00 | Window Closed / Lapsed |