Chemistry of Natural Compounds , Vol. 36, No. 5, 2000
TRITERPENOID GLYCOSIDES OF Fatsia japonica.
II. ISOLATION AND STRUCTURE OF GLYCOSIDES
FROM THE LEAVES
V. I. Grishkovets,1 E. A. Sobolev,1
A. S. Shashkov,2 and V. Ya. Chirva1
UDC 547.918:543.422
-L-arabinopyranosides of oleanolic and echinocystic acids and
The previously known triterpenoid 3-O-
hederagenin, 3-O- -D-glucopyranosyl-(1 2)-O- -L-arabinopyranosides of oleanolic acid and hederagenin,
in addition to 28-O- -L-rhamnopyranosyl-(1 4)-O- -D-glucopyranosyl-(1 6)-O- -D-glucopyranosyl ethers
of the 3-O- -L-arabinopyranoside of hederagenin, and 3-O- -D-glucopyranosyl-(1 2)-O- -L-
arabinopyranosides of oleanolic acid and hederagenin, respectively, are isolated from leaves of Fatsia
japonica (Araliaceae). The structures of the glycosides are confirmed by chemical methods and 13C NMR
spectroscopy.
Key words: Fatsia japonica, triterpenoid glycosides, NMR (13C, COSY, ROESY).
Leaves of Fatsia japonica Decne. et Planch (Araliaceae Juss.) are used in eastern folk medicine [1]. The composition
and structure of the triterpenoid glycosides of this plant have been previously studied by Japanese and Georgian scientists [2-6].
Preparative TLC of the alcohol extract of Fatsia japonica leaves revealed the presence of at least 14 triterpenoid
glycosides. This is significantly greater than the number of glycosides isolated earlier from the leaves of this plant [2-6].
Furthermore, various types of bonds were proposed in the literature for a single glycoside and only methylation was used and
not NMR spectroscopy, which enables the proposed structures to be determined unambiguously. We decided to study in detail
the glycosides of the leaves and to elucidate the structures of the glycosides using various modern NMR techniques.
The triterpenoid glycosides from the leaves were isolated by extraction of the defatted and ground dry raw material with
aqueous isopropanol followed by purification from strongly polar compounds (free sugars and salts) by dissolving the evaporated
extract in aqueous butanol and washing with water. The purified total triterpenoid glycosides were separated by chromatography
on silica gel using gradient elution by water-saturated CHCl —C H OH mixtures (10:1 1:1). This produced pure glycosides
3
2 5
A and B; fractions C and D; glycosides E and F; fractions G and H; and glycosides I, J, K, L, and M. Fraction C was separated
into pure glycosides C and C by rechromatography on silica gel with elution by CHCl —C H OH (4:1) saturated with aqueous
1
2
3
2 5
ammonia.
According to TLC, glycoside A was identical to an authentic sample of -sitosterol 3-O- -D-glucopyranoside [7].
Glycosides B (1), C (2), and C (3) were identical by TLC with authentic samples of the 3-O- -L-arabinopyranosides of
1
2
oleanolic and echinocystic acids and hederagenin, respectively [8]. The carbohydrate and aglycone compositions of these
glycosides were confirmed by TLC of the acid-hydrolysis products. The acid-hydrolysate of glycosides E (4) and F (5) contained
glucose and arabinose in both glycosides and aglycones, oleanolic acid and hederagenin, respectively. Furthermore, glycoside
5 according to TLC was identical to an authentic sample of hederagenin 3-O- -D-glucopyranosyl-(1 2)-O- -L-
arabinopyranoside, which was isolated by us from stalks and fruits of Crimean ivy [9, 10]. The spectra of the carbohydrate parts
of 4 and 5 are very similar. The chemical shifts correspond completely with the literature for the disaccharide -D-Glcp-(1 2)-
O- -L-Arap bound to oleanolic acid or hederagenin [9, 11, 12]. Chemical shifts in spectra of the aglycones of 4 and 5 also
correspond with the literature for 3-O-substituted oleanolic acid and hederagenin [9, 11, 12]. Thus, glycosides E and F are
1) V. I. Vernadskii Tavricheskii National University, 95007, Simferopol , ul. Yaltinskaya, 4; 2) N. D. Zelinskii Institute
of Organic Chemistry, Russian Academy of Sciences, 117913, Moscow, B-334, Leninskii prospekt, 47. Translated from
Khimiya Prirodnykh Soedinenii, No. 5, pp. 395-398, September-October, 2000. Original article submitted November 14, 2000.
0009-3130/00/3605-0501$25.00 ©2001 Plenum Publishing Corporation
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