US3636058A
Expired / Lapsed
US
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7 10 - dihydro - 3 - alkyl - 6h - dibenzo(b d) pyran-6 9(8h)-diones and 5-hydroxy-7-alkyl-4-chromanones
Assignee: F Hoffmann La Roche AG
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Filing: 1969-03-13
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Granted: 1972-01-18
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Expires: 1989-03-13
Abstract
Abstract 7,10-DIHYDRO - 3 - ALKYL-6H-DIBENZO(B,D)PYRAN-6,6(8H)DIONES WHICH ARE INTERMEDIATES FOR THE PHYSCHOTROPIC AND ANALGESIC 3-ALKYL - 9 - HYDROCARBYL(IDENE) - 6H - DIBENZO (B,D)PYRANS, 5-HYDROXY-7-ALKYL-4-CHROMANONES ARE ALTERNATE PATHWAY INTERMEDIATES IN THE PRODUCTION OF THE FINAL PRODUCT DIBENZO(B,D)PYRANS.
Inventors
- 👤 Kenneth Earl Fahrenholtz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:04
CPC Classifications
C; C07; C07D; C07D311/00; C07D311/02; C07D311/78; C07D311/80; C07D311/04; C07D311/06; C07D311/08; C07D311/16; C07D311/22
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) | 1975-01-17 | 1975-07-19 | 1976-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-17 | 1979-07-19 | 1980-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-17 | 1983-07-19 | 1984-01-18 | $7700.00 | Window Closed / Lapsed |