US3879411A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ditetrazolyl-benzodipyrans
Assignee: Fisons Ltd
•
Filing: 1972-07-24
•
Granted: 1975-04-22
•
Expires: 1992-07-24
Abstract
Abstract There are described compounds of formula I, in which one or more adjacent pairs of P, Q, R and T may represent a chain AND THE REMAINDER OF P, Q, R and T may represent a variety of groups. The compounds are indicated for use in the treatment of asthma.
Inventors
- 👤 Hugh Cairns
- 👤 Robert Minshull
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:51
CPC Classifications
C; C07; C07D; C07D405/00; C07D405/14
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
5 words
A COMPOUND OF FORMULA 1,
Claim 2
Dependent Claim
5 words
A COMPOUND OF FORMULA 1,
Claim 3
Dependent Claim
5 words
A compound of formula I,
Claim 4
Dependent Claim
5 words
A compound of formula I,
Claim 5
Dependent Claim
9 words
A compound according to claim 1, which is 4,10-Dioxo-2,8-ditetrazol-5''-yl-5-methoxy-4H,1OH-benzo(1,2-b:3,4-b'')dipyran.
References Cited (Backward Citations)
US3706768A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-21 | 1978-10-21 | 1979-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-21 | 1982-10-21 | 1983-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-21 | 1986-10-21 | 1987-04-22 | $7700.00 | Window Closed / Lapsed |