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Flavone synthesis

Ceroplastol synthesis, 1, 428 Cetyl alcohol synthesis, 1, 478 Chaetoglobasins structures, 4, 376 Chalcone, o -azido-2 -oxy-synthesis, 3, 823 Chalcone, 2-hydroxy-reduction, 3, 751 Chalcone, 2 -hydroxy-mass spectra, 3, 618 Chalcone dibromides flavone synthesis from, 3, 823 Chalcones polymers, 1, 304 Chanoclavine synthesis, 6, 423 Charge density waves in stacks of ions, 1, 351-352 Chartreusin... [Pg.577]

BAKER VENKATARAMAN Flavone synthesis Rearrangement of aromatic keto esters ot phenols to tiavones... [Pg.14]

The Auwers flavone synthesis consists of treatment of dibromo-coumarones 1 with alcoholic alkali to give the flavonols 2. It can also be described as the three-step sequence of 3 — 6. [Pg.262]

There is no published mechanistic study on the Auwers flavone synthesis. The mechanism may involve the nucleophilic addition of oxonium 7, derived from 1, with hydroxide to give 8. Base-promoted ring opening of 8 could provide the putative intermediate 9, which then could undergo an intramolecular Michael addition to form 10. Expulsion of bromide ion from 10 would then give flavonol 2. [Pg.262]

In summary, the Auwers flavone synthesis has seen only very limited utility in organic synthesis. [Pg.264]

The first enantioselective synthesis of cis- and trans- 3-hydroxyflavanones is based on the Lewis-acid-catalysed reaction of phenylmethanethiol with chalcone epoxides <96CC2747>. Further support for the intermediacy of epoxides in the Algar-Flynn-Oyamada flavone synthesis has been provided by the isolation of epoxides in the corresponding preparation of 3-hydroxy-2-phenylquinol-4-ones <96JCS(P2)269>. [Pg.299]

Citrus species are well-known for their accumulation of flavone- and flavanone-glycosides, and thus should contain all of the enzyme activities necessary for the synthesis of these compounds. Two tentative consensus sequences for FNS-II have been identified by in silico analysis of the CitEST database, apparently representing the first identification of putative FNS-II genes in this genus [29]. Biochemical determination of function and analysis of the proteins encoded by these genes will be an important step toward elucidating flavone synthesis in Citrus. [Pg.77]

Further illustrations of the value of isoxazole and Heck methodologies in flavone synthesis have been published (95ACS524) and a route to 3-aminoflavone-8-acetic acid has been described (95TL1845). The use of an imidazolidinone chiral auxiliary enables isoflavans to be formed in good yield and in high enantiomeric excess from phenacyl chlorides (95CC1317). [Pg.286]

BAKER - VENKATARAMAN Flavone synthesis Rearrangement 0/ aromatic keto esters ol phenols to Navones... [Pg.11]

BAER FISCHER Ammo sugar synthesis 10 BAEYER Oxindolesynthesis It BAEYER Oiarylmethane synthesis 11 BAEYER Pyridine synthesis 12 BAEYER - DREWSON Indoxyt synthesis 12 BAEYER VILLIGER Ketone oxidation 13 BAEYER - VILLIGER Tntylation 13 BAKER - VENKATARAMAN Flavone synthesis t4... [Pg.223]

Song, G.-Y., Ahn, B.-Z. Synthesis of dibenzoylmethanes as intermediates for flavone synthesis by a modified Baker-Venkataraman rearrangement. Arch. Pharm. Res. 1994, 17, 434 37. [Pg.542]


See other pages where Flavone synthesis is mentioned: [Pg.580]    [Pg.626]    [Pg.627]    [Pg.9]    [Pg.261]    [Pg.262]    [Pg.580]    [Pg.626]    [Pg.627]    [Pg.12]    [Pg.223]    [Pg.626]    [Pg.627]    [Pg.12]    [Pg.16]    [Pg.698]    [Pg.580]    [Pg.626]    [Pg.627]    [Pg.223]    [Pg.239]   
See also in sourсe #XX -- [ Pg.269 , Pg.270 , Pg.538 ]

See also in sourсe #XX -- [ Pg.306 ]




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AUWERS Flavone synthesis

BAKER - VENKATARAMAN Flavone synthesis

Flavone

Flavone ring synthesis

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