Flavonoid sulphate

Flavonoid sulphates such as quercetin 3,7-di-O-methyl 3-sulphate and kaempferol 7-0-methyl 3-sulphate, which inhihited the growth of Mycobacterium tuberculosis and Klebsiella pneumoniae, were isolated from the -hutanol fraction of 80% methanol extract of Argyreia speciosa (Burm. f) Boj. (Convolvulaceae), while flavonoids with mti-Helicobacter pylori activity, such as quercetin 3-methyl ether (isorhamnetin) (Fig. 3), were isolated from Cistus laurifolius L. (Cistaceae). ... 

Habbu PV, Mahadevan KM, Shastry RA, Manjunatha H. (2009) Antimicrobial activity of flavonoid sulphates and other fractions of Argyreia speciosa (Burm. f.) Boj. Indian J Exp Biol 47 121-128. 

Flamini, G., Pardini, M., and Morelli, I., A flavonoid sulphate and other compounds from the roots of Centaurea bracteata. Phytochemistry, 58, 1229, 2001. 

HARBORNE, J.B., Flavonoid sulphates a new class of sulphur compounds in higher plants. Phytochemistry, 1975,14, 1147-1155. 

Flavonoids do not affect the tropic responses, but bind to the NPA receptor [102]. Quercetin 10-3 binds the most strongly with a Kp = 1 pM. The 2,3-double bond is essential, the 3-OH enhances activity. Flavonoid sulphates [103] bind to the NPA receptor, but non-phenolic flavonoids and flavonoid glycosides do not [94]. 

Harborne, J. B. Flavonoid sulphates a new class of natural products of ecological significance in plants. Prog. Phytochem. 4, 189-208 (1977)... 

Barron, D. and Ibrahim, R.K. (1987) Synthesis of flavonoid sulphates. 1. Stepwise sulfation of position-3, position-7, and position-4 using n,n -dicyclohexylcarbodiimide and tatrabutylam-monium sulphate. Tetrahedron, 43, 5197-5202. 

Tea flavonoids, or tea extracts, are increasingly being added to foods. However, interactions with food and drink components remain unclear, and thus need to be carefully assessed in order that the full potential benefits from consuming tea, in whatever form, can be achieved. Meanwhile, tea catechins themselves undergo extensive O-methylation, glucuronidation, sulphation and ring fission... 

Yaga, A. et al., Antioxidative sulphated flavonoids in leaves of Polygonum hydropiper. Phytochemistry, 35, 885, 1994. 

Calanasan, C.A. and MacLeod, J.K., A diterpenoid sulphate and flavonoids from Wedelia asperrima. Phytochemistry, 47, 1093, 1998. 

Yagi, A., Uemura, T., Okamura, N., Haraguchi, H., Imoto, T., and Hashimoto, K., Antioxidative sulphated flavonoids in leaves of Polygonum hydropiper, Phytochemistry, 35, 885, 1994. 

De Santi, C. et al., Sulphation of resveratrol, a natural compound present in wine, and its inhibition by natural flavonoids, Xenobiotica, 30, 857, 2000. 

Mericli AH (1988) Flavonolignans, Kaempferol 3-Sulphate and Other Flavonoids from Silybum marianum subsp. anatolicum. Planta Med 44... 

Like a number of polyanionic compounds, including sulphated polysaccharides, polyhydroxycarboxylates and various tannins, the flavonoids that we tested seem to interact with the surface glycoprotein gpl20 to prevent binding of the virus to the sCD4 receptor (41). 

T1 rutin (Sf 0.45) chlorogenic acid R, — 0.5) hyperoside (1 , 0.6) isochloro-genic acid = Flavonoid test mixture T2 sparteine sulphate... 

Cnprie sulphate-citrate (sodium) (Benedict s reagent) for flavonoids and... 

Barron D, Varin LV, Ibrahim RK, Harbome JB, Williams CA (1988) Sulphated flavonoids - an update. Phytochemistry 27 2375-2395... 

Flavonoids occur in a variety of structural forms. They are phenolic compounds with a basic C6-C3-C6 skeleton. The two phenyl rings may be linked by an open three carbon chain (chalcones), or by the three carbon chain formed into a five-membered (aurones) or the more usual six-membered heterocyclic ring (flavones and flavonols) (Fig. 2 and 3). Conveniently, the 3000 different flavonoids are divided into some 12 classes according to the oxidation level of the central Cs-unit. Most flavonoids occur in vivo as glycosides that may have an aliphatic or aromatic acyl substituent on the sugar moieties. Other flavonoids are conjugated with sulphate groups, and some flavonoids occur as dimers, trimers, and polymers. 

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