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US4031098A
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Camptothecin analogues
Assignee: Shionogi and Co Ltd
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Filing: 1976-01-05
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Granted: 1977-06-21
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Expires: 1996-01-05
Abstract
Abstract Camptothecin analogues showing more potent anti-tumor activity than a naturally occurring alkaloid camptothecin, which also exhibit an immunosuppressive activity, in which the 1-ethyl of camptothecin is replaced by various members of substitutents such as alkyls (except ethyl), alkenyls, alkynyls, aralkyls or aryloylalkyls; being produced from readily accessible starting materials on totally synthetic method newly developed by the present inventor.
Inventors
- 👤 Tsutomu Sugasawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:08
CPC Classifications
C; C07; C07D; C07D491/00; C07D491/22
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
13 words
A compound of the formula: ##STR4## wherein R is allyl, propargyl or benzyl.
Claim 2
Dependent Claim
13 words
A compound of the formula: ##STR4## wherein R is allyl, propargyl or benzyl.
Claim 3
Dependent Claim
10 words
A compound as claimed in claim 1, namely 1-allyl-1-hydroxy-1,2,5,7-tetrahydro-4H-pyrano[ 3,4-f]indolizino[1,2-b]-quinoline-2,5-dione.
Claim 4
Dependent Claim
10 words
A compound as claimed in claim 1, namely 1-hydroxy-1-propargyl-1,2,5,7-tetrahydro-4H-pyrano[ 3,4-f]indolizino[1,2-b]-quinoline-2,5dione.
Claim 5
Dependent Claim
10 words
A compound as claimed in claim 1, namely 1-benzyl-1-hydroxy-1,2,5,7-tetrahydro-4H-pyrano[ 3,4-f]indolizino[1,2-b]-quinoline-2,5-dione.
References Cited (Backward Citations)
US3894029A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-20 | 1980-12-20 | 1981-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-20 | 1984-12-20 | 1985-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-20 | 1988-12-20 | 1989-06-21 | $7700.00 | Window Closed / Lapsed |