US2715625A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing 4-amino uracils
Assignee: Pfizer Inc
•
Filing: 1952-01-30
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Granted: 1955-08-16
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Expires: 1972-01-30
Abstract
No abstract record available.
Inventors
- 👤 Iii Charles E Maxwell
- 👤 Charles J Salivar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:00
CPC Classifications
C; C07; C07D; C07D239/00; C07D239/02; C07D239/24; C07D239/28; C07D239/46; C07D239/52; C07D239/54; C07D239/545
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
34 words
IN A PROCESS FOR PREPARING 1,3-DIMETHYL-4-AMINO-5NITROSOURACIL, THE IMPROVEMENT WHICH COMPRISES COMMINGLING AT ELEVATED TEMPERATURES APPROXIMATELY EQUIMOLAR PROPORTIONS OF DIMETHYLUREA AND CYANOACETIC ACID IN ACETIC ANHYDRIDE CONTAINING A MINOR PROPORTION OF AN ALKALINE CONDENSATION CATALYST.
References Cited (Backward Citations)
US2553022A
Cited
US2523496A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-08-15 | 1959-02-14 | 1959-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-08-15 | 1963-02-14 | 1963-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-08-15 | 1967-02-14 | 1967-08-16 | $7700.00 | Window Closed / Lapsed |