Patent US2543972A successfully refreshed from Google Patents.
US2543972A
Expired / Lapsed
US
⏱️ 0.0 years remaining
1,4-disubstituted piperazines
Assignee: Wyeth Holdings LLC
•
Filing: 1947-11-12
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Granted: 1951-03-06
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Expires: 1967-11-12
Abstract
No abstract record available.
Inventors
- 👤 Hultquist Martin Everett
- 👤 Howard Kenneth Leon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:10
CPC Classifications
C; C07; C07D; C07D239/00; C07D239/02; C07D239/24; C07D239/28; C07D239/32; C07D239/42; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/72; C07D213/74; C07D241/00; C07D241/02; C07D241/10; C07D241/14; C07D241/20; C07D277/00; C07D277/02; C07D277/20; C07D277/32; C07D277/38; C07D277/42
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
6 words
1,4-DISUBSTITUTED PIPERAZINE OF THE TYPE FORMULA
Claim 2
Dependent Claim
6 words
1,4-DISUBSTITUTED PIPERAZINE OF THE TYPE FORMULA
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) | 1954-03-05 | 1954-09-04 | 1955-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-03-05 | 1958-09-04 | 1959-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-03-05 | 1962-09-04 | 1963-03-06 | $7700.00 | Window Closed / Lapsed |