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US4057550A Expired / Lapsed US ⏱️ 0.0 years remaining

Nitrogen-containing polycyclic compounds

Assignee: Richter Gedeon Vegyeszeti Gyar Nyrt
•
Filing: 1975-09-17
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Granted: 1977-11-08
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Expires: 1995-09-17
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Abstract

Abstract New compounds of the general formula (I) <IMAGE> (I) wherein R1 stands for alkyl and R2 stands for carboxy, a functional carboxy derivative or a group convertible into carboxy group or a functional derivative thereof, have been prepared by reducing a compound of the general formula <IMAGE> (II) wherein R1 and R2 each have the same meanings as defined above and X- represents an anion derived from an acid, and optionally subjecting the obtained compound to hydrolysis. If desired, the racemic compounds of the general formula (I) can be resolved to yield the corresponding optically active isomers. The free bases of the general formula (I) can be converted into their pharmaceutically acceptable salts, or the salts can be treated with an alkaline agent to yield the free bases.

Inventors

  • 👤 Csaba Szantay
  • 👤 Lajos Szabo
  • 👤 Gyorgy Kalaus
  • 👤 Egon Karpati
  • 👤 Laszlo Szporny

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 17:47
CPC Classifications
C; C07; C07D; C07D461/00; A; A61; A61P; A61P9/00; A61P9/08

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 1 words
14,15-Dihydro-14-cyano-eburnamenine-(3β,16α).
Claim 2
Dependent Claim 1 words
14,15-Dihydro-14-cyano-eburnamenine-(3β,16α).
Claim 3
Dependent Claim 1 words
14,15-Dihydro-14-cyano-21-ethyl-eburnamenine-(3β,16α).
Claim 4
Dependent Claim 1 words
14,15-Dihydro-14-cyano-21-ethyl-eburnamenine-(3β,16α).

References Cited (Backward Citations)

US3454583A Cited
US3925392A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-11-07 1981-05-09 1981-11-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-11-07 1985-05-09 1985-11-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-11-07 1989-05-09 1989-11-08 $7700.00 Window Closed / Lapsed

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