Chemistry of Natural Compounds, Vol. 47, No. 4, September, 2011 [Russian original No. 4, July-August, 2011]
A NEW FLAVONE GLYCOSIDE FROM THE AERIAL
PART OF Scutellaria schachristanica
Z. O. Tashmatov, K. A. Eshbakova,*
and Kh. M. Bobakulov
UDC 547.972
The new flavone glycoside schachristanoside was isolated from the aerial part of Scutellaria schachristanica
Zuz. (Lamiaceae). Spectral data and chemical transformations found that schachristanoside had the structure
chrysin-7-O-ꢀꢁ-L-arabinopyranosyl-(1ꢂ6)]-ꢃ-D-glucopyranoside.
Keywords: Scutellaria schachristanica Zuz. (Lamiaceae), flavonoid, chrysin, schachristanoside, PMR, 13C, and
DEPT spectra.
In continuation of chemical research on the aerial part of Scutellaria schachristanica Zuz. (Lamiaceae) collected
during flowering in Samarkand Oblast, Republic of Uzbekistan [1, 2], we isolated a new bioside of chrysin. Herein we report
the structure of 1, which we called schachristanoside.
OH
O
O
HO
OH
O
1
O
13
HO
HO
O
7
9
1
1
OH
3
15
1
0
5
OH
O
1
The IR spectrum of 1 showed absorption bands consistent with the presence of aromatic double bonds (1613.98,
492.53) and ꢄ-pyrone carbonyl (1656.01). The presence of the latter was confirmed by the resonance for C-4 at 182.20 ppm
1
13
in the C NMR spectrum [3]. The UV spectrum of 1 (MeOH, ꢅmax, nm): 272, 307; +CH COONa, 270, 309) was characteristic
3
of flavone derivatives [4]. This was confirmed by the PMR spectrum, which contained resonances for eight aromatic protons
that were very characteristic of the chrysin spectrum, two anomeric protons, and the other protons of the carbohydrate part.
Therefore, the studied compound was a bioside.
Acid hydrolysis of the new flavonoid glycoside 1 produced chrysin (5,7-dihydroxyflavone) (2), C H O , mp 290–
1
5 10 4
2
92°C [1]. Paper chromatography (PC) detected L-arabinose (3) and D-glucose (4) in the carbohydrate part of the hydrolysate.
1
3
We concluded from a study of the PMR and C NMR spectra of 1 (Table 1), which contained the same set of
resonances for the H and C atoms of the monosaccharide units, that the new flavonoid glycoside was in fact a bioside of
chrysin and contained D-glucose and L-arabinose in a 1:1 ratio.
The anomeric protons resonated in the PMR spectrum of 1 as doublets at ꢆ 5.10 ppm with SSCC J = 7.32 Hz
(
D-glucose H-1) and ꢆ 4.90 with SSCC J = 7.33 Hz (L-arabinose H-1). These facts indicated that the monosaccharides
4
D-glucose and L-arabinose had the pyranose form and C -conformation and, therefore, the ꢃ- and –ꢁ-configurations,
1
respectively [5].
The chemical shifts of the carbohydrate resonances in the PMR and 13C NMR spectra (Table 1) showed that 1 was a
monodesmoside with a pentose in the terminal position [6].
S. Yu. Yunusov Institute of the Chemistry of Plant Substances,Academy of Sciences, Republic of Uzbekistan, Tashkent,
fax (99871) 120 64 75, e-mail: e_komila@yahoo.com. Translated from Khimiya Prirodnykh Soedinenii, No. 4, July–August,
2
011, pp. 487–488. Original article submitted January 31, 2011.
0
009-3130/11/4704-0547 ©2011 Springer Science+Business Media, Inc.
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