Patent EP0052086A1 successfully refreshed from Google Patents.
EP0052086A1
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EP
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Process for producing flavone derivatives with medicinal activity
Assignee: Glaxo Allen SpA
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Filing: 1981-11-05
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Granted: —
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Expires: 2001-11-05
Abstract
Abstract A process for producing flavone derivative of formula:, in which R is hydrogen or a disaccharide radical, R 1 is -OH or -OCH 3 ; R 2 is H or -OH; starting from flavone-7-glucosides of formula by total acetylation with acetiv anhydride and pyridine, and selective dehydrogenation in the 2-3 position with SeO 2 in a molar excess of about 10:1, in isoamyl alcohol solution.
Inventors
- 👤 Claudio Redaelli
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 17:55
CPC Classifications
C; C07; C07H; C07H17/00; C07H17/04; C07H17/06; C07H17/065; C07H17/07; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/22; C07D311/26; C07D311/28; C07D311/32
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
136 words
A process for producing flavone derivatives of formula in which R is hydrogen or a disaccharide radical; R 1 is -OH or -OCH 3 ; R 2 is H or -OH. starting from floavanone-7-glucosides of formula : in which R, R 1 , R 2 are as heretofore defined, by means of: a) total acetylation of the flavanone-7-glucoside by heating to 90-100°C for about 5 hours with acetic anhydride and pyridine; b) selective dehydrogenation in the 2-3 position by means of SeO 2 in a approximately 10:1 molar excess over the flavanone, in an isoamyl alcohol solution heated under reflux; c) total deacetylation by means of alkaline hydrolysis with dilute inorganic bases under hot conditions; d) possible elimination of the gluooside radical by means of acid hydrolysis with strong dilute mineral acids under hot oondi- tions.
Claim 2
Dependent Claim
136 words
A process for producing flavone derivatives of formula in which R is hydrogen or a disaccharide radical; R 1 is -OH or -OCH 3 ; R 2 is H or -OH. starting from floavanone-7-glucosides of formula : in which R, R 1 , R 2 are as heretofore defined, by means of: a) total acetylation of the flavanone-7-glucoside by heating to 90-100°C for about 5 hours with acetic anhydride and pyridine; b) selective dehydrogenation in the 2-3 position by means of SeO 2 in a approximately 10:1 molar excess over the flavanone, in an isoamyl alcohol solution heated under reflux; c) total deacetylation by means of alkaline hydrolysis with dilute inorganic bases under hot conditions; d) possible elimination of the gluooside radical by means of acid hydrolysis with strong dilute mineral acids under hot oondi- tions.
Claim 3
Dependent Claim
13 words
A process as claimed in claim 1, wherein diosmin is prepared from hesperidin.
Claim 4
Dependent Claim
13 words
A process as claimed in claim 1, wherein apigenin is prepared from naringin.
Claim 5
Dependent Claim
24 words
A process as claimed in claim 1, wherein the deacetylation by alakline hydrolysis is carried out with 15% NaOH at 100°C for 10 minutes.
Claim 6
Dependent Claim
30 words
A process as claimed in claim 1, wherein the elimination of the glucoside radical by adid hydrolysis is carried out with 18% dilute sulphuric acid under reflux for 4-5 hours.
References Cited (Backward Citations)
FR2255894A1
Cited
FR2402655A1
Cited
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