Kaempferol 7-glycosides

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. 

Quercus ilex Leaf hairs Acylated kaempferol glycosides 102... 

Mitrokotsa, D. et al., Bioactive compounds from the buds of Platanus orientalis and isolation of a new kaempferol glycoside, Planta Med., 59, 517, 1993. 

Fiorini, C. et al., Acylated kaempferol glycosides from Laurus nobilis leaves. Phytochemistry, 47, 821, 1998. 

Flavonols occur mainly as O-glycosides and the diversity of the glycoside moiety in this group is noteworthy with about 200 different quercetin and kaempferol glycosides described to date [19]. Table 6 reports the most common flavonols. 

Kaempferol glycoside (3,5,7,4 -tetrahydroxyflavone glycoside) Limocitrin 3-3-D-glucoslde (3,5,7,4 -tetrahydroxy-8,3 -dimethoxy-flavone 3-3-D glucoside)... 

Flavonoid and phenolic glycoside are other classes of phytoconstituents commonly found in the plants of genus Aconitum. Three new glycoside derivatives of flavonoid (compounds 12-14) were reported by Shrestha et al. (2006) as quercetin and kaempferol glycosides with two to five sugar units (Figure 4). 

Four glycoside derivatives of phenol (Figure 5) have been also reported from Aconitum naviculare they are kaempferol glycosides (15 and 16) and phenylpropanoids glycosides (17 and 18) (DalFAcqua et al., 2008). Such types of glycoside derivatives of phenol are relatively common in several plant species. 

The chemistry is characterised by a number of phenolic constituents, including flavonoids (Hyperoside, spireoside, kaempferol glycoside), salicylates (salicylalde-hyde, gaultherin, methylsalicylate, salicin, salicylic acid), tannins (water-soluble, hydrolysable types, also some catechols). The volatile oil contains salicylates, benzaldehyde, ethylbenzoate, heliotropin, phenylacetate and vanillin. 

Quercetin and kaempferol glycosides (0.05%) kaempferoi-O-dirhamnoside, k-3-0-genliotrioside, kdriglucoside gossypetin-dimethylefher... 

Fig. I7A Equisetum arvense (1) is characterized by the yellow-orange zone of isoquercitrin (R, 0.6/T 1), two blue zones above (e.g. caffeic acid) and three weak blue or green zones blow (R[ 0.4-0.55, e.g. galiiteolin/T2). The official horsetail does not contain green kaempferol glycoside zones in the lower R, range which indicate one of the adulterants (see Fig. 18). Alkaloids are absent or in extremely low concentrations only.

Equisetum palustre (3,4) six green zones of kaempferol glycosides in the R, range 0,05-0.5, such as k-3-diglucosyl-7-glucoside, k-3-rutinosyl-7-glucoside and k-3, 7, diglucoside. 

Equisetum silvaticum (6) similar pattern of green kaempferol glycoside zones as in sample 5. In addition, the yellow-orange zones of quercetin-3, 7-diglucoside (R, 0.4) and isoquercitrin (R, — 0.7) as in E. arvense (1,2). 

In a study on the antioxidant effects of the components from H. diffusa on xanthine-xanthine oxidase cytochrome c, Lu et al. found that quercetin 3-0-sambubioside (22) and quercetin 3-0-sophoroside (23) are superoxide radical scavengers. The kaempferol glycoside (18) and the itidoid glycosides having cinnamoyl or feruloyl substituents on the glucose units [(31) and (33)], as well as asperuloside (48), were found to be inactive in this assay [29]. 

H-1-Benzopyran-4-one, 3-(P-D-glucopyranosyloxy)-5,7-dihydroxy-2-(4-hydroxyphenyl)- kaempferol glycoside ... 

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