7-O-rutinosides

The plant is known elaborate a series of quite unusual phenanthrene alkaloid derivatives, of which aristoliukine-C, aristofolin A and E, aristolochic acid-la methyl ester, and aristolochic acid. Other chemical constituents found in this plant are flavonoid glycosides such as kaempferol-3-O-rutinoside and quercetin kaempferol-3-O-rutinoside (3,4). Exposure to Aristolochiaceae family is associated with the development of cancer in humans. A significant advance is the toxicological effects of aristolochic acid has been provided by the work of Pezzuto et al. They showed that aristolochic acid is a mutagen... 

Figure 1 Structures of (A) ginkgolide A, ginkgolide B, bilobalide, (B) flavonolgly-cosides (R=H kaempferol-3-O-rutinoside R=OH quercetin-3-O-rutinoside R=0CH3 isorhamnetin-3-O-rutinoside) and (C) ginkgolic acids (R=Ci3H27, C15H31, C15H29, C15H33).

Licania apetala var. apetala (E. May) Fritsch is a tree native to the Amazonian forest. Its leaves were extracted with the same method used for L. licaniaeflora. From the n-butanol extract of the leaves seven flavonoids were obtained quercetin 3-0- 3-D-galactopyranoside (6), quercetin 3-O-a-L-rhamnopyranoside (8) quercetin 3-O-rutinoside (18), quercetin 3-0-a-L-arabinopyranoside (9), taxifolin 3-O-a-L-rhamnopyranoside (64), myricetin 4 -O-a-L-rhamnopyranoside (66), and kaempferol 3-O-rutinoside (67), [see Fig. (1), (2), (7), and (8)] [18]. 

Quercctin-3-O-rutinoside. on the other hand, is the main flavonol in... 

Anthocyanins such as cyanidin-3-O-rutinoside, cyanidin-3-O-glucoside, and peonidin- 3- (9- ruLinoside (Fig. 1.22) have also been reported in sweet cherries (Prunus avium) and sour cherries (Prunus cerasus) [Wu et al., 2004]. 

Plums (Prunus domestica) and peaches are also a rich source of cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside [Crozier et al., 2006c],... 

Ginkgoaceae (1 > 6) p)-glucoside, quercitrin, isoquercitrin, rutin, k-7-O-gIucoside, k- -O-rutinoside, astragalin, dihydrokaempferol-7-O-gliicoside, isorhamnetin-3-O-rutinoside... 

Our investigation on Malaysian H. diffusa [31] as well as H. her-bacea also yielded quercetin 3-0-glucopyranoside (21) together with quercetin 3-0-rutinoside (24). From H. herbacea, we have found kaempferol 3-O-rutinoside (25), kaempferol 3-O-glucoside (26), kaempferol 3-O-arabinopyranoside (27) and quercetin 3-0-galactoside (28) [7]. We have also reported kaempferitrin (29) from H. verticillata [32] and isovitexin (30) from the aerial parts of H. dichotoma [33]. 

In our own study on H. diffusa using chemical-based assays such as the ferric thiocyanate (FTC), thiobarbituric acid (TBA), and diphenylpicrylhydrazyl (DPPH) radical-scavenging methods [31], we found that both quercetin 3-0-/ -glucopyranoside (21) and quercetin 3-O- -rutinoside (22) inhibited linoleic acid peroxidation and also exhibited good DPPH radical-scavenging properties (87-88%) which was comparable to vitamin C (93%). We also found asperuloside to be inactive in both assays. 

---