Chemistry of Natural Compounds, Vol. 44, No. 3, 2008
FLAVONOIDS FROM Gossypium hirsutum FLOWERS
T. Wu,1,2 R. Abdulla,1,2 Y. Yang,1,2 and H. A. Aisa1*
UDC 547.972
L. (Malvaceae) is a cotton species that is widely cultivated worldwide. In Xinjiang Autonomous
Gossypium hirsutum
Region (PRC), flowers of
are used in folk medicine. The plant is officially listed as a Chinese Medicinal Herb and
G. hirsutum
is used as a sedative agent and to treat delayed mental development and to improve brain function [1]. We studied the flavonoid
composition of flowers of
.
G. hirsutum
(2 kg) were extracted with ethanol (95%, 3 times). The extracts were combined and evaporated
Flowers of
G. hirsutum
to dryness at reduced pressure to afford dry powder (400 g) that was fractionated over a column of ion-exchange resin AB-8
(weakly polar). Compounds were eluted from the column by water and aqueous ethanol (50 and 70%). The alcohol fractions
(90 g) were rechromatographed over a column of silica gel to produce 1-7.
Kaempferol-3-O-β-D-(6″-O-p-coumaryl)glycoside (1), light-yellow powder, mp 246-248°C (MeOH). UV spectrum
(λ , MeOH, nm): 226, 268, 316, 352sh.
max
PMR spectrum (600 MHz, DMSO-d , δ, ppm, J/Hz): 5.46 (1H, d, J = 7.8, H-1″), 6.12 (1H, d, J = 16.2, H-8′″), 6.16
6
(1H, d, J = 1.8, H-6), 6.39 (1H, d, J = 1.8, H-8), 6.79 (2H, d, J = 8.4, H-3′″,5′″), 6.86 (2H, d, J = 9.0, H-3′,5′), 7.35 (1H, d,
J = 16.2, H-7′″), 7.38 (2H, d, J = 8.4, H-2′″,6′″), 8.00 (2H, d, J = 9.0, H-2′,6′), 10.03, 10.17 (1H each, br.s, OH on C-4′″ and
C-4′, respectively), 10.86 (1H, br.s, 7-OH), 12.59 (1H, s, 5-OH).
13
C NMR spectrum (150 MHz, DMSO-d , δ, ppm): 177.6 (C-4), 166.4 (C-9′″), 164.4 (C-7), 161.4 (C-5), 160.2 (C-4′),
6
160.0 (C-4′″), 156.6 (C-2), 156.5 (C-9), 144.8 (C-7′″), 133.2 (C-3), 131.0 (C-2′,6′), 130.4 (C-2′″,6′″), 125.1 (C-1′″), 121.0
(C-1′), 116.0 (C-3′,5′), 115.3 (C-3′″,5′″), 113.8 (C-8′″), 104.1 (C-10), 101.1 (C-1″), 99.0 (C-6), 93.9 (C-8), 76.4 (C-3′), 74.4
(C-5″), 74.3 (C-2″), 70.1 (C-4″), 63.2 (C-6″) [2].
Quercetin (2), yellow powder, mp >300°C (acetone). UV spectrum (λ , MeOH, nm): 256, 374.
max
PMR spectrum (600 MHz, DMSO-d , δ, ppm, J/Hz): 6.19 (1H, d, J = 1.8, H-6), 6.41 (1H, d, J = 2.4, H-8), 6.88 (1H,
6
d, J = 8.4, H-5′), 7.55 (1H, q, J = 8.4, 2.4, H-6′), 7.68 (1H, d, J = 2.4, H-2′), 9.32 (1H, s, 4′-OH), 9.39 (1H, s, 3-OH), 9.61 (1H,
s, 3′-OH), 10.79 (1H, s, 7-OH), 12.50 (1H, s, 5-OH).
13
C NMR spectrum (150 MHz, DMSO-d , δ, ppm): 93.55 (C-8), 98.38 (C-6), 103.21 (C-10), 115.80 (C-2′), 116.39
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(C-5′), 120.17 (C-6′), 122.15 (C-1′), 135.95 (C-3), 145.26 (C-3′), 146.99 (C-2), 147.91 (C-4′), 156.32 (C-9), 160.92 (C-5),
164.09 (C-7), 176.05 (C-4) [3].
Quercetin-3′-O-β-D-glucoside (3), yellow powder, mp 183-184°C (MeOH). UV spectrum (λ , MeOH, nm): 252,
max
370.
PMR spectrum (600 MHz, DMSO-d , δ, ppm, J/Hz): 3.17-5.09 (sugar protons), 5.15 (1H, d, J = 4.2, H-1″), 6.19 (1H,
6
d, J = 1.8, H-6), 6.49 (1H, d, J = 1.8, H-8), 6.98 (1H, d, J = 8.4, H-5′), 7.85 (1H, q, J = 8.4, 2.4, H-6′), 7.96 (1H, d, J = 1.8, H-2′),
9.22 (1H, s, 4′-OH), 9.42 (2H, s, 3-OH), 10.67 (1H, s, 7-OH), 12.46 (1H, s, 5-OH).
13
C NMR spectrum (150 MHz, DMSO-d , δ, ppm): 60.76 (C-6″), 69.73 (C-4″), 73.49 (C-2″), 76.14 (C-3″), 77.42
6
(C-5″), 93.90 (C-8), 98.44 (C-6), 102.59 (C-1″) 103.22 (C-10), 115.93 (C-2′), 116.20 (C-5′), 122.42 (C-6′), 123.77 (C-1′),
136.20 (C-3), 145.49 (C-3′), 146.43 (C-2), 148.98 (C-4′), 156.39 (C-9), 160.84 (C-5), 164.22 (C-7), 176.13 (C-4) [4, 5].
Quercetin-3-O-β-D-glucoside (4), yellow powder, mp 249-250°C (MeOH). UV spectrum (λ , MeOH, nm): 257,
max
361.
1) Xinjiang Technical Institute of Physics and Chemistry, Academyof Sciences of the PRC, Urumchi, 830011, China,
fax (86991) 383 56 79, e-mail: haji@ms.xjb.ac.cn; 2) Graduate School of the PRC, Beijing, 100039, PRC. Translated from
Khimiya Prirodnykh Soedinenii, No. 3, pp. 296-297, May-June, 2008. Original article submitted April 3, 2008.
0009-3130/08/4403-0370 ©2008 Springer Science+Business Media, Inc.
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