US3431252A
Expired / Lapsed
US
⏱️ 0.0 years remaining
5,5-dialkyl-d-ribofuranosyl purine compounds and intermediates
Assignee: Merck and Co Inc
•
Filing: 1966-04-01
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Granted: 1969-03-04
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Expires: 1986-04-01
Abstract
No abstract record available.
Inventors
- 👤 Edward Walton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:59
CPC Classifications
C; C07; C07H; C07H13/00; C07H13/02; C07H13/08; C07H19/00; C07H19/02; C07H19/04; C07H19/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-03-03 | 1972-09-02 | 1973-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-03-03 | 1976-09-02 | 1977-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-03-03 | 1980-09-02 | 1981-03-04 | $7700.00 | Window Closed / Lapsed |