Glycosides flavone

Scheme 1.—Conversion of a Flavone Glycoside into the Corresponding Chalcone and Dihydrochalcone Analogs.

A detailed study of the flavonoid chemistry of the island endemics, the closely related G. tinctoria, and live additional species from the mainland provided additional evidence pointing toward G. tinctoria as the ancestral species (Pacheco et al., 1993). The flavonoid profiles of all species consisted of flavonol glycosides as major components with an unidentified flavone glycoside and several unidentified phenolic compounds (presumably not flavonoids). The pattern of distribution of the flavonol glycosides and unidentified flavones within the set of nine species proved to be extremely informative. (The phenols were ubiquitous and are not considered further.) Kaempferol glycosides were seen in neither the island species nor G. tinctoria, but were present, in several combinations, in the rest of the mainland taxa. The isorhamnetin glycosides showed the reverse pattern, with one exception the island endemics and G. tinctoria exhibited these compounds, whereas four of the other mainland species did not. The sole exception is G. boliviari, which exhibited one of the isorhamnetin derivatives. 

Polygonum orientale, roots, stems, leaves Flavone glycosides 83... 

Some herbs are standardized for several active constituents, while others are standardized to a single active ingredient. St. John s wort is standardized to contain 0.3% hypericin, whereas ginkgo is standardized to contain 24% flavone glycosides and 6% ter-pene lactones. However, standardizing an herb product to one or more plant component(s) that are identifiable by assay may be incorrect. Many herbalists believe that the whole plant contributes to the efficacy and that there are many unknown active compounds in each plant [6]. 

Jenkins KM, Jensen PR, Fenical W (1998) Bioassays with marine microorganisms. In Haynes KF, Millar JG (eds) Methods in chemical ecology bioassay methods. Kluwer Academic, pp 1-37 Jensen PR, Jenkins KM, Porter D, Fenical W (1998) Evidence that a new antibiotic flavone glycoside chemically defends the sea grass Thalassia testudinum against zoosporic fungi. Appl Environ Microb 64 1490-1496... 

A simple TLC method has been developed for the separation and identification of flavons and flavon glycosides in the extract of Phillyrea latifolia L. The leaves (100 g) were defatted in 11 of chloroform for 24 h and then extracted with 2 X 11 of ethanol-water (80 20, v/v). The collected extracts were concentrated and extracted again with n-hexane to remove chlorophylls and other apolar constituents. Analytes were extracted with ethyl acetate. Both normal phase and RP-TLC have been used for the separation of flavonoids. The results are compiled in Table 2.36. It was concluded from the data that TLC can be successfully applied for the quality control of plant extracts containing various flavone derivatives [124],... 

TLC DATA OF THE ISOLATED COMPOUNDS AND OF FLAVONE, FLAVONE GLYCOSIDE AND BIFLAVONE REFERENCE STANDARDS... 

Compound Texton Flavone glycosides 6-OH Flavone, glycosides Flavone, C-glyco sides... 

A. Pieroni, D. Heimler and Y. Huand, A TLC method for the separation and identification of flavons and flavon glycosides from biflavons in vegetable extract. J. Plan. Chromatogr.—Mod. TLC. 11 (1998) 230-232. 

Yadava RN, Tiwari L. (2007) New antifungal flavone glycoside from Butea monosperma O. Kuntze. J Enzyme Inhib Med Chem 22 497-500. 

More nsnal vegetables were stndied by Nnntila et al. [358] who characterized onions and spinach for the phenolic composition, with and without previous hydrolysis. The authors performed the simultaneous determination of phenolic acids, flavonols, flavones glycosides, and cathechins. Fignre 19.9 reprodnces the separation obtained for the standard mixture in this study. 

Albach, D.C. et al., Acylated flavone glycosides from Veronica, Phytochemistry, 64, 1295, 2003. 

Farag, S.F. et al., Isoflavonoids and flavone glycosides from rhizomes of Iris carthaliniae. Phytochemistry, 50, 1407, 1999. 

Keki, S., Deak, G., and Zsuga, M., Fragmentation study of rutin, a naturally occurring flavone glycoside cationized with different alkali metal ions, using post-source decay matrix-assisted laser desorption/ionization mass spectrometry, J. Mass Spectrom., 36, 1312, 2001. 

There are few studies on vacuolar importation of flavonoids other than anthocyanins and PAs. Klein et al. reported uptake of flavone glycosides by isolated H. vulgare primary leaf vacuoles via a vacuolar H -ATPase linked mechanism,and by vacuoles from Secale cereale (rye) mesophyll via a possible ABC transporter mechanism. Li et al. "" found medicarpin conjugated to glutathione was also sequestered by an ABC transporter mechanism. 

Kitanaka, S. and Takido, M., Studies on the constituents of the leaves of Cassia torosa 3. The structures of two new flavone glycosides, Chem. Pharm. Bull, 40, 249, 1992. 

Damu, A.G. et al., A flavone glycoside from Andrographis alata, Phytochemistry, 49, 1811, 1998. 

TABLE 13.1 New Flavone Glycosides — continued Glycoside Source Family Ref. 

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