US2646434A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing delta4-pregnenes
Assignee: Wyeth Holdings LLC
•
Filing: 1952-04-03
•
Granted: 1953-07-21
•
Expires: 1972-04-03
Abstract
No abstract record available.
Inventors
- 👤 Bernstein Seymour
- 👤 Milton D Heller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:08
CPC Classifications
C; C07; C07J; C07J5/00; C07J75/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
9 words
A METHOD OF PREPARING THE COMPOUND HAVING THE FORMULA:
Claim 2
Independent Claim
9 words
A METHOD OF PREPARING THE COMPOUND HAVING THE 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) | 1956-07-20 | 1957-01-19 | 1957-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-20 | 1961-01-19 | 1961-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-20 | 1965-01-19 | 1965-07-21 | $7700.00 | Window Closed / Lapsed |