Cynaroside
Introduction '''Cynaroside''' (also known as '''luteoloside''') is a flavone, a flavonoid-like chemical compound. It is a 7-O-glucoside of luteolin.
Natural occurrences It can be found in ''Ferula varia'' and ''F. foetida'' in ''Campanula persicifolia'' and ''C. rotundifolia'', in the bamboo ''Phyllostachys nigra'', and in ''Teucrium gnaphalodes''. ; In foodIt can be found in dandelion (the highest concentration in the flowers, but also in the roots) and in ''Cynara scolymus'' (artichoke).
Metabolism Flavone 7-O-beta-glucosyltransferase adds a glucose to luteolin.A cynaroside 7-O-glucosidase has been identified in the artichoke.
Spectral data  UV-Vis Lambda-max UV : 348, 260 nm Extinction coefficient (log ε): 4.11, 4.23  IR Major absorption bands ? cm−1 NMR Proton NMR  1H-NMR (500 MHz, CD3COCD3 + D2O):δ 3.42 (1H, t, J = 9.0 Hz, H-4′), 3.49 (1H, t, J = 9.0 Hz, H-2″), 3.56 (1H, t, J = 9.0 Hz, H-3″), 3.60 (1H, m, H-5″), 3.68 (1H, dd, J = 12.2, 5.6 Hz, H-6a″), 3.85 (1H, dd, J = 12.2, 1.8 Hz, H-6b″), 5.10 (1H, d, J = 7.8 Hz, H-1″), 6.44 (1H, d, J = 1.8 Hz, H-6), 6.63 (1H, s, H-3), 6.83 (1H, d, J = 1.8 Hz, H-8), 6.95 (1H, d, J = 8.0 Hz, H-5′), 7.41 (1H, d, J = 8.0 Hz, H-6′), 7.43 (1H, bs, H-2′) Carbon-13 NMR  13C-NMR (125 MHz, CD3COCD3 + D2O): δ 61.7 (C-6″), 70.3 (C-4″), 73.8 (C-2″), 76.8 (C-3″), 77.4 (C-5″), 95.8 (C-8), 100.5 (C-6), 100.7 (C-1″), 103.7 (C-3), 106.3 (C-10), 113.8 (C-2″), 116.5 (C-5′), 120.3 (C-6′), 122.6 (C-1′), 146.3(C-3′), 150.4 (C-4′), 158.0 (C-9), 161.8 (C-5), 163.9 (C-7), 165.8(C-2), 183.1 (C-4) Other NMR data  MS Masses of main fragments ESI-MS M+H+ m/z 449.1
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