Chemistry of Natural Compounds, Vol. 39, No. 3, 2003
PHENOLIC COMPOUNDS FROM Urtica urens
GROWING IN GEORGIA
N. Sh. Kavtaradze
UDC 547.992
The chemical composition of the aerial part of stinging nettle (Urtica urens L.) collected in Adigen region (Georgia)
during flowering (June 2002) was investigated.
Compound 1 was isolated from the CHCl extract of the aqueous alcohol extract of the aerial part of the plant by
3
chromatography over a silica-gel column with elution by CHCl :CH OH with increasing CH OH content.
3
3
3
Compound 1 was a crystalline white solid, mp 203-205°C. UV spectrum (λ , CH OH, nm): 230, 255, 300, 345;
max
3
-1
(
KOH): 245, 390. IR spectrum (νmax, KBr, cm ): 3340, 3140 (OH), 1740 (α-pyrone), 1615, 1570, 1520 (benzene ring).
Monoacetate, mp 176-178°C. Compound 1 gave no melting-point depression when mixed with an authentic sample of
scopoletin. The chromatogram contained one inseparable spot characterized as 6-methoxy-7-hydroxycoumarin (scopoletin) [1,
2
].
Fractionation over a polyamide sorbent of the aqueous alcohol extract remaining after CHCl extraction produced a
3
fraction eluted with ethanol (45%). It was condensed. The amorphous powder was chromatographed over a polyamide column
with elution by CHCl and CHCl :ethylacetate with increasing ethylacetate concentration to afford compounds 2 and 3.
3
3
Compound 2 was a white crystalline solid, mp 195-197°C. UV spectrum (λmax, CH OH, nm): 240, 300, 325. Caustic
3
fusion with KOH produced protocatechuic acid with R 0.80 (n-butanol:acetic acid:water, 4:2:1). The diacetyl derivative of 2
f
had mp 198-200°C.
Compound 3 wasawhitecrystallinesolid, mp203-205°C. UV spectrum (λmax, CH OH, nm): 240, 330; (CH COONa):
3
3
20
3
34; (C H ONa): 380, 260; (H BO +CH COONa): 375, 260; (AlCl ): 360, 320, 245; [α]
-32.0° (c 1.0, CH OH). The
2
5
3
3
3
3
D
3
pentaacetyl derivative of3 melts at 185-187°C. Caustic fusion produced protocatechuic acid; acid hydrolysis, quinic and caffeic
acids. The fact that a lactone was not formed indicates that the caffeic acid was bonded to quinic acid at the 3-position [3].
The physicochemical properties, UV and IR spectra, and samples mixed with authentic compounds are consistent with
2
and 3 being caffeinic and chlorogenic acids, respectively [4, 5].
REFERENCES
1.
2.
3.
4.
5.
N. F. Komissarenko, P. P. Khvorost, and V. D. Ivanov, Khim. Prir. Soedin., 102 (1983).
M. D. Alaniya, I. I. Moniava, N. F. Komissarenko, and E. P. Kemertezidze, Khim. Prir. Soedin., 239 (1972).
H. Fischer and G. Dangschat, Chem. Ber., 65, 1009 (1932).
L. I. Dranik, Khim. Prir. Soedin., 303 (1966).
V. A. Bandyukova, G. N. Zemtsova, N. V. Sergeeva, and V. I. Frolova, Khim. Prir. Soedin., 388 (1970).
I. G. Kutateladze Institute of Pharmaceutical Chemistry, Academy of Sciences of Georgia, fax (99532) 25 00 26.
Translated from Khimiya Prirodnykh Soedinenii, No. 3, p. 248, May-June, 2003. Original article submitted June 6, 2003.
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009-3130/03/3903-0314$25.00 2003 Plenum Publishing Corporation
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