US3948895A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synthesis of 3,5-diaminopyrazinoic acid from 3,5-diamino-2,6-dicyanopyrazine and intermediates
Assignee: EIDP Inc
•
Filing: 1972-03-06
•
Granted: 1976-04-06
•
Expires: 1992-03-06
Abstract
Abstract An improved method for the preparation of 3,5-diaminopyrazinoic acid (which is useful for the manufacture of diuretics) is described. New compounds obtained in the process include 3,5-diamino-2,6-dicarbamoylpyrazine; 3.5-diamino-6-carbamoylpyrazinoic acid and 3,5-diamino-6-carbamoylpyrazine. The latter compounds are also useful as curing agents for epoxy resins.
Inventors
- 👤 Dennis S. Donald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:18
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/26
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
19 words
A compound of the formula ##SPC10## wherein R is [--COOH, --CONH 2 or --H] --COOH or --CONH 2 .
Claim 2
Dependent Claim
19 words
A compound of the formula ##SPC10## wherein R is [--COOH, --CONH 2 or --H] --COOH or --CONH 2 .
Claim 3
Dependent Claim
11 words
The compound of claim 1 where R = COOH; 3,5-diamino-6-carbamoylpyrazinoic acid.
Claim 4
Dependent Claim
12 words
The compound of claim 1 where R = CONH 2 ; 3,5-diamino-2,6-dicarbamoylpyrazine.
References Cited (Backward Citations)
US3017412A
Cited
US3313813A
Cited
US3345372A
Cited
US3544568A
Cited
DE2216925A1
Cited
US3814757A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |