Patent US2554986A successfully refreshed from Google Patents.
US2554986A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synthesis of pregnenolone
Assignee: Pharmacia and Upjohn Co
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Filing: 1950-01-05
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Granted: 1951-05-29
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Expires: 1970-01-05
Abstract
No abstract record available.
Inventors
- 👤 Frederick W Heyl
- 👤 Milton E Herr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:57
CPC Classifications
C; C07; C07J; C07J5/00; C07J75/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
28 words
THE PROCESS WHICH INCLUDES: FORMING A 22-ENOL ESTER BY HEATING A 3-ACYLOXY-BISNOR-5CHOLEN-22-A1 WITH AN ENOL ESTERIFYING AGENT AT A TEMPERATURE BETWEEN ABOUT 60 AND ABOUT 150 DEGREES CENTRIGRADE.
Claim 2
Dependent Claim
28 words
THE PROCESS WHICH INCLUDES: FORMING A 22-ENOL ESTER BY HEATING A 3-ACYLOXY-BISNOR-5CHOLEN-22-A1 WITH AN ENOL ESTERIFYING AGENT AT A TEMPERATURE BETWEEN ABOUT 60 AND ABOUT 150 DEGREES CENTRIGRADE.
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) | 1954-05-28 | 1954-11-27 | 1955-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-05-28 | 1958-11-27 | 1959-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-05-28 | 1962-11-27 | 1963-05-29 | $7700.00 | Window Closed / Lapsed |