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US3963732A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for preparing dihydroxydiphenylmethane derivatives

Assignee: Individual
•
Filing: 1974-08-21
•
Granted: 1976-06-15
•
Expires: 1994-08-21
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Abstract

Abstract There is provided a new process for the preparation of esters of 4,4'-dihydroxydiphenyl-(2-pyridyl)-methane of the general formula: ##SPC1## which Wherein R 1 is a hydrogen atom or a sulpho group or an acyl radical and R 2 is a hydrogen atom or a carboalkoxy radical, and the salts thereof with pharmaceutically-acceptable, non-toxic inorganic and organic bases. Those compounds in wich R 2 is a carboalkoxy radical are new.

Inventors

  • 👤 Tiberio Bruzzese
  • 👤 Rodolfo Ferrari

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 00:39
CPC Classifications
C; C09; C09B; C09B11/00; C09B11/04; C09B11/26

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 114 words
A process for the preparation of an ester of the formula ##SPC6## in which R 1 is a hydrogen atom or a suphoxy group or is alkanoyl having up to 6 carbon atoms and Me is a pharmaceutically acceptable inorganic or organic non-toxic cation, wherein a compound of the formula ##SPC7## in which Me and R 1 have the same meaning as above, is selectively hydrolyzed and then decarboxylated, in a basic medium to produce the objective compound I wherein R 1 is hydrogen or a sulphoxy group and, when desired, acylating said compound with an organic acid to produce a compound I wherein R 1 is alkanoyl having up to 6 carbon atoms.
Claim 2
Dependent Claim 114 words
A process for the preparation of an ester of the formula ##SPC6## in which R 1 is a hydrogen atom or a suphoxy group or is alkanoyl having up to 6 carbon atoms and Me is a pharmaceutically acceptable inorganic or organic non-toxic cation, wherein a compound of the formula ##SPC7## in which Me and R 1 have the same meaning as above, is selectively hydrolyzed and then decarboxylated, in a basic medium to produce the objective compound I wherein R 1 is hydrogen or a sulphoxy group and, when desired, acylating said compound with an organic acid to produce a compound I wherein R 1 is alkanoyl having up to 6 carbon atoms.
Claim 3
Dependent Claim 22 words
A process according to claim 1 wherein R 1 is alkanoyl having up to 6 carbon atoms having up to 6 carbons.
Claim 4
Dependent Claim 18 words
A process according to claim 1 wherein the hydrolysis and decarboxylation takes place in an aqueous basic medium.
Claim 5
Dependent Claim 33 words
A process according to claim 1 wherein the compound II is subjected to a selective hydrolysis and decarboxylation reaction in a boiling dilute aqueous sodium hydroxide solution for a period of 1 hour.
Claim 6
Dependent Claim 19 words
A process according to claim 4 wherein the dilute aqueous solution hydroxide solution contains 3% of sodium hydroxide therein.
Claim 7
Dependent Claim 35 words
A process according to claim 1 wherein the compound II is subjected to a selective hydrolysis and decarboxylation reaction in a solution of potassium tert.-butylate in dimethylsulphoxide at 100°C for a period of 1 hour.

References Cited (Backward Citations)

GB879247A Cited
US3558643A Cited
GB1241782A Cited
US3873551A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-06-15 1979-12-15 1980-06-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-06-15 1983-12-15 1984-06-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-06-15 1987-12-15 1988-06-15 $7700.00 Window Closed / Lapsed

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