EXPERIMENTAL
We used solvent systems CHCl —CH OH (9:1) (1) and n-butanol—pyridine—water (6:4:3) (2).
3
3
Preparative TLC used LSL 5/40 µm silica gel (Chemapol, Czech Rep.). TLC was performed on Silufol UV-254 plates.
Compounds were visualized on TLC in UV light using ammonia vapor. Sugar was detected on PC (Filtrak No. 12) by spraying
with acidic anilinium phthalate with heating for 3-5 min at 90-100oC.
Conditions for recording spectra have been published [9].
Extraction and Isolation of Flavonoids. Dried and ground fruit (0.2 kg) of zeravschan juniper that was collected in
autumn 1996 on slopes near Kumyshkan (Tashkent) was extracted with ethanol (95%) in a Soxhlet apparatus for 4 h. The
alcohol extract was condensed until dry. Then, recrystallization from methanol gave 1 (0.09 g). Preparative TLC of the mother
liquor in system 1 gave 2 (0.07 g).
Zeravschanoside (1). C21H20O13, mp 328-330oC (methanol). UV spectrum (EtOH, max, nm): 276, 343; CH CO Na
3
2
275, 345. IR spectrum (KBr, max, cm-1): 3445 (OH), 1665 (C O of -pyrone), 1600, 1560, 1510 (aromatic C C), 1095, 1030
(C–O of glycosides).
PMR spectrum ( , ppm, J/Hz, C D N): 3.50-4.50 (carbohydrate protons), 5.53 (1H, d, J = 7.0, H-1 ), 6.86 (1H, s, H-3),
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5
7.12 (1H, d, J = 9.0, H-5 ), 7.63 (1H, dd, J = 9.0, J = 2.0, H-6 ), 8.06 (1H, d, J = 2.0, H-2 ).
Zeravschanoside Nonaacetate (1a). Glycoside 1 (15 mg) was dissolved in pyridine (1 mL) and acetic anhydride
(2 mL), worked up as usual after 3 h, and recrystallized from ethanol to produce 1a (14 mg), C39H38O22, mp 248-250oC. Mass
+
spectrum, m/z: M 858, 331, 329, 318, 271, 169, 109, etc.
Acid Hydrolysis of 1. Glycoside 1 (18 mg) was hydrolyzed by aqueous-methanolic HCl (20 mL, 5%) for 4 h on a
boiling-water bath. Then, the methanol was evaporated in vacua. The precipitated aglycone was filtered off and recrystallized
o
+
from methanol. Yield of 5,6,7,8,3 ,4 -hexahydroxyflavone, 8 mg, mp >360 C, C15H10O8 (M 318). D-Glucose was observed
in the hydrolysate by PC using system 2.
Isoquercitrin 2. C21H20O12, mp 238-239oC. UV spectrum (EtOH, max, nm): 255, 265 , 362. IR spectrum (KBr,
,
*
max
cm-1): 3450 (OH), 1660 (C O of -pyrone), 1618, 1575, 1518 (aromatic C C), 1075, 1026, 1009 (C–O of glycosides). PMR
spectrum ( , ppm, J/Hz, C D N): 3.65-4.44 (sugar protons), 5.47 (1H, d, J = 7.0, H-1 ), 6.51 (1H, d, J = 2.0, H-6), 6.59 (1H,
5
5
d, J = 2.0, H-8), 7.21 (1H, d, J = 8.5, H-5 ), 7.86 (1H, dd, J = 2.0, J = 8.5, H-6 ), 8.11 (1H, br.s, H-2 ), 13.78 (1H, br.s, 5-OH).
+
Acid hydrolysis of 2 (5% HCl, 4 h) formed D-glucose and quercetin (3,5,7,3 ,4 -pentahydroxyflavone), C15H10O7 (M
302), mp 313-315oC, UV spectrum (MeOH, max, nm): 257, 268, 371; CH CO Na 270, 405.
3
2
o
+
Acetylation of 2 (acetic anhydride and pyridine) gave the octaacetate, mp 200-202 C (M 770 and peaks for fragments
of tetraacetylhexose with m/z 331, 271, and 169).
REFERENCES
1.
2.
L. K. Klyshev, V. A. Bandyukova, and L. S. Alyukina, Plant Flavonoids [in Russian], Nauka, Alma-Ata (1978).
Kh. Kh. Kholmatov, I. A. Kharlamov, and P. K. Alimbaeva, Principal Medicinal Plants of Middle Asia [in
Russian], Meditsina, Tashkent (1984).
3.
4.
Flora of Uzbekistan [in Russian], Tashkent (1941), Vol. 1, p. 111.
T. J. Mabry, K. R. Markham, and M. B. Thomas, The Systematic Identification of Flavonoids, Springer-Verlag,
Berlin (1970), p. 146, 329.
5.
6.
Y. Kikuchi, Y. Miyaichi, Y. Yamaguchi, H. Kisu, and T. Tomimori, Chem. Pharm. Bull., 39, 1047 (1991).
K. R. Markham, Isolation Techniques for Flavonoids, in: The Flavonoids, J. B. Harborne, ed., Chapman and Hall,
London (1975), p. 2-44.
7.
8.
9.
N. K. Kochetkov and O. S. Chizhov, Mass Spectrometry of Carbohydrates [in Russian], in: Methods of
Carbohydrate Research [in Russian], Mir, Moscow (1975).
Sh. V. Abdullaev, A. Sattikulov, E. Kh. Batirov, Yu. V. Kurbatov, and V. M. Malikov, Khim. Prir. Soedin., 104
(1983).
M. P. Yuldashev, Khim. Prir. Soedin., 193 (2001).
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