Quercetin-3-O-rutinoside

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]. 

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. 

Rutin (3,3, 4, 5,7-pentahydroxyflavone 3-0-rutino-side, quercetin 3-O-rutinoside C. I. 75730, natural yellow 10). 

Quercetin-3-O-rutinoside) G. uralensis G. uralensis (HPLC) G. echinata G. echinata (HPLC)... 

Figure 9a. Quercetin (26), quercetin-3-O-rutinoside (rutin. 27), orientin-X -0-glucoside (28), isosohaftoside (29), schaftoside (30) and vitexin-2 -0-P-D-glucoside (31).

Figure 7.18 Quercetin-3-O-rutinoside, P -carotene and protodioscin occur in asparagus.

Figure 7.21 Green tomatoes contain the steroidal alkaloid tomatine. Levels decline in ripe fruit which contain the carotenoids lycopene, fS-carotene and lutein. Quercetin-3-O-rutinoside, naringenin and 5-O-caffeoylquinic acid are also present.

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