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US4778891A
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Certain pyrano (3,4-f)-indolizine derivatives
Assignee: Daiichi Pharmaceutical Co Ltd
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Filing: 1986-10-16
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Granted: 1988-10-18
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Expires: 2006-10-16
Abstract
Abstract A pyranoindolizine derivative represented by the following general formula (I): ##STR1## wherein R means a hydrogen atom or hydroxyl group and Q denotes >C═O or ##STR2## with a proviso that Q is other than >C═O when R is a hydrogen atom. Its preparation process is also described.
Inventors
- 👤 Hiroaki Tagawa
- 👤 Hirofumi Terasawa
- 👤 Akio Ejima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:25
CPC Classifications
C; C07; C07D; C07D493/00; C07D493/12; C07D493/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
41 words
A pyranoindolizine derivative represented by the following general formula (I): ##STR20## wherein R is a hydrogen atom or hydroxyl group and Q is >C═O or ##STR21## with a proviso that Q is other than >C═O when R is a hydrogen atom.
Claim 2
Dependent Claim
41 words
A pyranoindolizine derivative represented by the following general formula (I): ##STR20## wherein R is a hydrogen atom or hydroxyl group and Q is >C═O or ##STR21## with a proviso that Q is other than >C═O when R is a hydrogen atom.
Claim 3
Dependent Claim
10 words
A pyranoindolizine derivative represented by the following formula (I*b): ##STR22##
Claim 4
Dependent Claim
10 words
A pyranoindolizine derivative represented by the following formula (I*b): ##STR22##
Claim 5
Dependent Claim
10 words
A pyranoindolizine derivative represented by the following formula (I*c): ##STR23##
Claim 6
Dependent Claim
10 words
A pyranoindolizine derivative represented by the following formula (I*c): ##STR23##
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) | 1991-10-18 | 1992-04-18 | 1992-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-18 | 1996-04-18 | 1996-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-18 | 2000-04-18 | 2000-10-18 | $7700.00 | Window Closed / Lapsed |