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US2776969A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of preparation of cyclopentanophenanthrene derivatives

Assignee: Syntex SA
•
Filing: 1953-02-17
•
Granted: 1957-01-08
•
Expires: 1973-02-17
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Abstract

No abstract record available.

Inventors

  • 👤 Rosenkranz George
  • 👤 Djerassi Carl

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 04:13
CPC Classifications
C; C07; C07J; C07J71/00; C07J75/00

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 18 words
A COMPOUND SELECTED FROM THE GROUP CONSISTING OF $5-SIROSTEN-3B,11A-DIOL, LOWER FATTY ACID ESTERS AND BENZOIC ACID ESTERS THEREOF.

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) 1960-01-08 1960-07-09 1961-01-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1964-01-08 1964-07-09 1965-01-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1968-01-08 1968-07-09 1969-01-08 $7700.00 Window Closed / Lapsed

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