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US2824876A Expired / Lapsed US ⏱️ 0.0 years remaining

Production of 4-mercaptonicotinic acid and intermediate therefor

Assignee: Schenley Industries Inc
•
Filing: 1955-02-23
•
Granted: 1958-02-25
•
Expires: 1975-02-23
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Abstract

No abstract record available.

Inventors

  • 👤 Katz Leon
  • 👤 Murray S Cohen
  • 👤 Schroeder William

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 16:10
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/78; C07D213/79; C07D213/80; C07D213/86; C07D213/87; C07D213/88; C07D495/00; C07D495/02; C07D495/04

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 36 words
A PROCESS FOR THE PRODUCTION OF 4-MERCAPTONICOTINIC ACID WHICH COMPRISES THE REACTION OF 4-HYDROXYNICOTINIC ACID WITH PHOSPHORUS PENTASULFIDE TO FORM 5-AZA-1,2,3BENZODITHIOLE-3-THIONE, ALKALINE HYDROLYSIS OF THE RESULTING COMPOUND, AND SUBSEQUENT RE-RECOVERY OF 4-MERCAPTONICOTINIC ACID FROM THE HYDROLYZATE.
Claim 2
Dependent Claim 36 words
A PROCESS FOR THE PRODUCTION OF 4-MERCAPTONICOTINIC ACID WHICH COMPRISES THE REACTION OF 4-HYDROXYNICOTINIC ACID WITH PHOSPHORUS PENTASULFIDE TO FORM 5-AZA-1,2,3BENZODITHIOLE-3-THIONE, ALKALINE HYDROLYSIS OF THE RESULTING COMPOUND, AND SUBSEQUENT RE-RECOVERY OF 4-MERCAPTONICOTINIC ACID FROM THE HYDROLYZATE.

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) 1961-02-24 1961-08-26 1962-02-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-02-24 1965-08-26 1966-02-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-02-24 1969-08-26 1970-02-25 $7700.00 Window Closed / Lapsed

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