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Flavones and flavone synthases
Phytochemistry, 2005Within the secondary metabolite class of flavonoids which consist of more than 9000 known structures, flavones define one of the largest subgroups. Their natural distribution is demonstrated for almost all plant tissues. Various flavone aglyca and their O- or C-glycosides have been described in the literature.
Martens, S., Mithöfer, A.
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Flavones and flavone glycosides from Halophila johnsonii
Phytochemistry, 2008Halophila johnsonii Eiseman is a shallow-water marine angiosperm which contains UV-absorbing metabolites. Studies on methanol extracts of H. johnsonii by means of HPLC-UV, NMR, HPLC-MS resulted in isolation and identification of seven previously unknown flavone glycosides: 5,6,7,3',4',5'-hexahydroxyflavone-7-O-beta-glucopyranoside (1), 5,6,7,3',4',5 ...
Yanhui, Meng +4 more
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Acta Crystallographica Section C Crystal Structure Communications, 2000
In the title molecule, C15H11NO4S, the phenyl and benzene rings are quite planar, with maximum deviations from planarity of 0.009 (2) and 0.004 (1) A, respectively. The γ-pyrone ring deviates from planarity and makes a dihedral angle of 8.3 (3)° with the 2-phenyl substituent. The sulfonamide group is involved in N—H⋯O hydrogen bonding.
E, Kendi, S, Ozbey, O, Bozdağ, R, Ertan
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In the title molecule, C15H11NO4S, the phenyl and benzene rings are quite planar, with maximum deviations from planarity of 0.009 (2) and 0.004 (1) A, respectively. The γ-pyrone ring deviates from planarity and makes a dihedral angle of 8.3 (3)° with the 2-phenyl substituent. The sulfonamide group is involved in N—H⋯O hydrogen bonding.
E, Kendi, S, Ozbey, O, Bozdağ, R, Ertan
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Structure of the flavone hymenoxin
Acta Crystallographica Section C Crystal Structure Communications, 19912-(3,4-Dimethoxyphenyl)-5,7-dihydroxy-6,8-dimethoxy-4H-chromen-4-o ne, C19H18O8, Mr = 374.38, monoclinic, P2(1)/n, a = 9.026(4), b = 15.054(6), c = 12.829(6) A, beta = 100.98(4) degrees, V = 1711(1) A3, Z = 4, Dx = 1.450 g cm-3, lambda (Mo K alpha) = 0.71073 A, mu = 1.07 cm-1, F(000) = 784, T = 295 K, R = 0.0778 for 2280 independent reflections.
W H, Watson +3 more
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The biological potential of flavones
Natural Product Reports, 2010Covering: 1990 to 2009 Flavones are well known for their antioxidant activity, and are unique in that they are present in the majority of fruits and vegetables. The majority of metabolic diseases are speculated to originate from oxidative stress, and it is therefore significant that recent studies have shown the positive effect of flavones ...
Alok Kumar, Verma, Ram, Pratap
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Flavones: A direct synthesis of 6-hydroxy-flavones
Proceedings of the Indian Academy of Sciences - Section A, 19516-Hydroxy-flavones have been synthesised by the Venkataraman oxidation of 2:5-dihydroxy-, 2:5:2′-trihydroxy-, 2:5:4′-trihydroxy chalkones as well as 6:3′-dihydroxy-flavanone by selenium dioxide. Thus the polyhydroxy-chalkones can be oxidised to the corresponding hydroxy-flavones in one step.
G. N. Vyas, N. M. Shah
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1982
Most reports on the identification of known flavonoids in new plant sources as well as those on novel flavonoids naturally deal with the two most abundant classes, the flavones and flavonols. For this chapter we have listed all references to the occurrence of flavone and flavonol aglycones which have appeared from 1975 to 1980, and also include such ...
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Most reports on the identification of known flavonoids in new plant sources as well as those on novel flavonoids naturally deal with the two most abundant classes, the flavones and flavonols. For this chapter we have listed all references to the occurrence of flavone and flavonol aglycones which have appeared from 1975 to 1980, and also include such ...
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HYDROXYMETHYLATION OF FLAVONES
Organic Preparations and Procedures International, 1991(1991). HYDROXYMETHYLATION OF FLAVONES. Organic Preparations and Procedures International: Vol. 23, No. 6, pp. 741-747.
György Litkei +3 more
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