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 food

It 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-maxUV : 348, 260 nm
Extinction coefficient(log ε): 4.11, 4.23
IR
Major absorption bands? cm−1
NMR
Proton NMR1H-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 NMR13C-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 fragmentsESI-MS [M+H]+ m/z 449.1