Patent US3887587A successfully refreshed from Google Patents.
US3887587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synthesis of prostaglandins of the one-series
Assignee: Pfizer Inc
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Filing: 1972-04-17
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Granted: 1975-06-03
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Expires: 1992-04-17
Abstract
Abstract In the synthesis of prostaglandins of the ''''one''''-series an alteration in the conventional reaction sequence avoids side reactions and provides an improved synthesis via a series of novel intermediates. In this improved synthesis the side chain at the 8 position is attached to the five membered ring before the side chain at the 12 position is attached.
Inventors
- 👤 Thomas K Schaaf
- 👤 Elias J Corey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:37
CPC Classifications
C; C07; C07C; C07C405/00; C07D; C07D309/00; C07D309/02; C07D309/08; C07D309/10; C07D309/12; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/55
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
5 words
A COMPOUND OF THE FORMULA:
Claim 2
Dependent Claim
5 words
A COMPOUND OF THE FORMULA:
Claim 3
Dependent Claim
5 words
A compound of the formula:
Claim 4
Dependent Claim
5 words
A compound of 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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |