US3721664A
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Preparation of 5-cytosine nucleosides
Assignee: F Hoffmann La Roche AG
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Filing: 1970-01-27
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Granted: 1973-03-20
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Expires: 1990-01-27
Abstract
Abstract Cytosine nucleosides are prepared by silylating cytosine or a 5substituted cytosine derivative, condensing the silyl derivative with an acylated sugar halide and saponifying the condensation product. The process is used in preparing known chemotherapeutically useful cytosine nucleosides, particularly the anti-viral 5-fluorocytosine arabinoside and 1- Beta -Darabino furanosyl-cytosine.
Inventors
- 👤 M Hoffer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:43
CPC Classifications
C; C07; C07H; C07H19/00; C07H19/02; C07H19/04; C07H19/06; C07F; C07F7/00; C07F7/02; C07F7/08; C07F7/18; C07F7/1804
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
6 words
A Beta -anomer of the formula:
Claim 2
Dependent Claim
12 words
The compound of claim 2 wherein said compound is 1-(2'',3'',5''-tri-O-benzoyl- Beta -arabinofuranosyl)-5-fluorocytosine.
Claim 3
Dependent Claim
12 words
The compound of claim 2 wherein said compound is 1-(2'',3'',5''-tri-O-benzoyl- Beta -D-arabinofuranosyl)-5-fluorocytosine.
Claim 4
Dependent Claim
12 words
The compound of claim 2 wherein said compound is 1-(2'',3'',5''-tri-O-benzoyl- Beta -D-arabinofuranosyl)-cytosine.
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) | 1976-03-19 | 1976-09-18 | 1977-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-19 | 1980-09-18 | 1981-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-19 | 1984-09-18 | 1985-03-20 | $7700.00 | Window Closed / Lapsed |