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US2525223A
Expired / Lapsed
US
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Preparation of n-substituted piperazines
Assignee: Wyeth Holdings LLC
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Filing: 1948-05-25
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Granted: 1950-10-10
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Expires: 1968-05-25
Abstract
No abstract record available.
Inventors
- 👤 Kenneth L Howard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:07
CPC Classifications
C; C07; C07D; C07D295/00; C07D295/02; C07D295/023
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
9 words
A METHOD OF PREPARING COMPOUNDS HAVING THE GENERAL FORMULA:
Claim 2
Independent Claim
9 words
A METHOD OF PREPARING COMPOUNDS HAVING THE GENERAL FORMULA:
References Cited (Backward Citations)
DE657979C
Cited
US2427473A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-10-09 | 1954-04-10 | 1954-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-10-09 | 1958-04-10 | 1958-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-10-09 | 1962-04-10 | 1962-10-10 | $7700.00 | Window Closed / Lapsed |