Next Article in Journal
Comments on “Antibacterial Effect of Five Zingiberaceae Essential Oils” by Laohakunjit et al., Molecules 2007, 12, 2047-2060
Previous Article in Journal
A Standard Addition Method to Assay the Concentration of Biologically Interesting Polyphenols in Grape Berries by Reversed-Phase HPLC
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Communication

A New Sesquiterpene Glycoside from the Aerial Parts of Saussurea triangulata

Natural Products Laboratory, College of Pharmacy, Sungkyunkwan University, Suwon 440-746, Korea
*
Author to whom correspondence should be addressed.
Molecules 2007, 12(10), 2270-2276; https://doi.org/10.3390/12102270
Submission received: 17 September 2007 / Revised: 1 October 2007 / Accepted: 1 October 2007 / Published: 2 October 2007

Abstract

:
Column chromatographic separation of a MeOH extract of the aerial parts of Saussurea triangulata led to the isolation of a new sesquiterpene glycoside 6, together with three quinic acid derivatives, two phenolics, two sesquiterpene glycosides and two flavonoids. The new compound 6 was identified as amarantholidol A glycoside by spectroscopic and chemical methods.

Introduction

In a continuation of our study on biologically active compounds from Korean Compositae plants [1,2], the phytochemical constituents of the aerial parts of Saussurea triangulata were investigated. S. triangulata is widely distributed in Korea, and has been used in Korean folk medicine for the treatment of inflammation, hypertension and hepatitis [3]. However, there have been no phytochemical or bioactivity studies of this plant. Purification of the MeOH extract of the aerial parts from S. triangulata by column chromatography yielded a new compound 6, together with nine known compounds: three quinic acid derivatives 1 - 3, two phenolics 4 and 5, two sesquiterpene glycosides 7 and 8, and two flavonoids 9 and 10 (Figure 1). Their structures were determined by spectroscopic means. Compounds 1 - 4, 7, 9 and 10 were isolated from the genus Saussurea for the first time.
Figure 1. The structures of compounds 1 - 10.
Figure 1. The structures of compounds 1 - 10.
Molecules 12 02270 g001

Results and Discussion

By comparison of their spectral data (1H-, 13C-NMR and MS) with that reported in the literature, compounds 1-5 and 7-10 were identified as 3-caffeoylquinic acid (1) [4], methyl 4-caffeoylquinic acid (2) [5], methyl 5-caffeoylquinic acid (3) [6], 4-hydroxybenzoic acid (4) [7], syringin (5) [8], amarantholidoside II (7) [9], (-)-oplopan-4-one-10-α-O-β-D-glucoside (8) [10], 7,4'-di-O-methyl- apigenin 5-O-α-D-xylopyranosyl-(1→6)-β-D-glucopyranoside (9) [11,12] and 7-O-methylapigenin 5- O-α-D-xylopyranosyl-(1→6)-β-D-glucopyranoside (10), respectively [11].
Compound 6 was obtained as a colorless oil and [α]D value was -17.3° (c 0.85, MeOH). Its IR spectrum revealed absorption bands for hydroxyl (3397 cm-1) and C=C double bond functional groups (1642 cm-1), and the UV spectrum exhibited an absorption band at λmax 200 nm. The HRESI-MS spectrum of 6 showed a quasimolecular ion peak at m/z 457.2426 [M+Na]+, suggesting the molecular formula C21H38O9 (calc. for C21H38O9Na: 457.2408) and three degrees of unsaturation. The 1H-NMR spectrum showed an ABX system of olefinic protons [δ 5.26 (1H, dd, J = 16.5, 2.0 Hz), 5.03 (1H, dd, J = 10.5, 2.0 Hz) and 5.98 (1H, dd, J = 16.5, 10.5 Hz)], a single olefinic proton δ 5.16 (1H, d, J = 10.0 Hz), which account for two of the three degree of unsaturation, four methyl groups [δ 1.18, 1.15, 1.71 and 1.30 (each 3H, s)], three methylene groups [δ 1.99 (1H, dd, J = 14.5, 8.0 Hz), 1.66 (1H, dd, J = 14.5, 4.0 Hz), 2.30 (1H, ddd, J = 13.5, 10.0, 5.0 Hz), 2.11 (1H, ddd, J = 13.5, 9.0, 8.0 Hz), 1.76 (1H, m), and 1.41 (1H, m)], and two oxygenated methine protons [δ 4.92 (1H, ddd, J = 10.0, 8.0, 4.0 Hz) and 3.24 (1H, dd, J = 10.5, 2.0 Hz)]. The 13C-NMR spectrum showed four methyl groups (δ 26.0, 25.0, 17.2 and 28.7), three methylene groups (δ 48.4, 37.9 and 30.5), four oxygenated carbons (δ 74.2, 71.6, 79.0 and 73.9) and four olefinic carbons (δ 112.2, 146.5, 126.4 and 141.8). The spectral data all suggested that 6 was a nerolidol type sesquiterpene glycoside [9]. This was confirmed by the enzymatic hydrolysis of 6, which afforded 6a and a sugar component, which accounted for the last degree of unsaturation. The sugar was identified to be D-glucose by co-TLC (EtOAc-MeOH-H2O = 9:3:1, Rf value: 0.17) with a D-glucose standard. The 1H- and 13C-NMR spectrum also confirmed the presence of D-glucose [13]. The position of D-glucose was determined to be at C-5, based on the HMBC correlation (Figure 2). The configuration the sugar moiety was determined to be the β form by the presence of an anomeric proton at δ 4.25 (1H, d, J = 8.0 Hz, H-1’) and an anomeric carbon at δ 100.2 (C-1’) in the 1H- and 13C-NMR spectra, respectively. Comparison of the 1H-NMR spectrum (Table 1) and [α]25D value indicated a strong similarity between 6a and to the known compound amarantholidol A, which was previously isolated from Amaranthus retroflexus [9]. The configurations at C-5 and C-10 were the same (α-H form) as those of amarantholidol A and 7 based on the chemical shifts and J values. Thus, compound 6 was proposed to be amarantholidol A glycoside, which has been isolated from natural sources for the first time.
Figure 2. Important HMBC (H → C) correlations of 6.
Figure 2. Important HMBC (H → C) correlations of 6.
Molecules 12 02270 g002

Experimental

General

The melting points were determined on a Gallenkamp melting point apparatus and are uncorrected. The optical rotations were determined using a Jasco P-1020 polarimeter (Jasco Co., Japan). The IR spectra were recorded on a Bruker Vector 22 FT-IR spectrometer (Bruker Co., German). The UV spectra were obtained using a Shimadzu UV-1601 UV/Visible instrument (Shimadzu Co., Japan). The NMR spectra were recorded on a Varian VXR-500 instrument. The FAB-MS data were obtained using a JMS700 spectrometer (Jeol Co., Japan). The ESI-MS data were obtained using a Micromass QTOF2 LC/ESI MS (Micromass Co., USA). The semi-preparative HPLC was carried out on a Gemini® RP-C18 column (5 μ, 10×250 mm, Phenomenex Co., USA) using an RI detector (Shodex Co., Japan). Open column chromatography was carried out on silica gel (Silica gel 60, 70-230 mesh, Merck Co., Germany). Thin-layer chromatography (TLC) was performed on silica gel 60 F254 and RP-18 F254s (Merck Co., Germany). The packing material for the molecular sieve column chromatography was Sephadex LH-20 (Pharmacia Co., Sweden). Low pressure liquid chromatography was carried out using a LiChroprep Lobar®-A RP-18 column (240×10 mm, Merck Co., Germany) and a Duramat® 80 pump (CFG Prominent Co., Germany)

Plant material

The aerial parts of S. triangulata were collected at Mt. Odae, Korea in August, 2004. A voucher specimen (SKK-04-081) was deposited at the College of Pharmacy of Sungkyunkwan University.

Extraction and Isolation

The dried aerial parts of S. triangulata (1.1 kg) were extracted three times with 80% MeOH at room temperature. The resulting MeOH extract (160.0 g) was partitioned with solvent to give n- hexane (35.0 g), CHCl3 (12.0 g) and n-BuOH (22.0 g) soluble fractions. The n-BuOH fraction (22.0 g) was chromatographed over a Diaion HP-20 resin column using a gradient solvent system (MeOH - H2O = 0: 100 → 100:0) to give six fractions B1 - B6. The B2 fraction (2.0 g) was subjected to Sephadex LH-20 chromatography (MeOH - H2O = 80:20) to give five fractions B21 - B25. The B22 fraction (1.0 g) was subjected to RP-C18 silica column chromatogaphy (MeOH - H2O = 30:70) to afford two fractions B221 and B222. The B221 fraction (600.0 mg) was purified on a RP-18 Lobar®-A column (CH3CN - H2O = 10:90) to yield compounds 1 (200.0 mg), 2 (25.0 mg) and 3 (180.0 mg). The B222 fraction (300.0 mg) was purified on a RP-18 Lobar®-A column (CH3CN - H2O = 15:85) to yield compound 4 (10.0 mg). The B24 fraction (200.0 mg) was purified on a RP-18 Lobar®-A column (MeOH - H2O = 20:80) to give compound 5 (50.0 mg). The B3 fraction (3.0 g) was subjected to Sephadex LH-20 chromatography (MeOH - H2O = 80:20) to give five fractions B31 - B36. The B31 fraction (300.0 mg) was purified by RP-18 Lobar®-A chromatography (MeOH - H2O = 20:80) and semi-preparative HPLC (CH3CN - H2O = 20:80) to give 6 (15.0 mg). The B4 fraction (5.0 g) was subjected to Sephadex LH-20 (MeOH - H2O = 80:20) to give six fractions B41 - B46. The B41 fraction (1.0 g) was separated on a RP-C18 silica column (MeOH - H2O = 57:43) to give three fractions B411 - B413. The B411 fraction (350.0 mg) was purified by RP-18 Lobar®-A chromatography (MeOH - H2O = 50:50) and semi-preparative HPLC (CH3CN - H2O = 27:73) to give compounds 7 (8.0 mg) and 8 (10.0 mg). The B412 fraction (350.0 mg) was purified by recrystal1ization (100% MeOH) to give 9 (15.0 mg). The B5 fraction (2.0 g) was subjected to Sephadex LH-20 chromatography (MeOH - H2O = 80:20) to give five fractions B51 - B56. The B51 fraction (500.0 mg) was purified by recrystal1ization (100% MeOH) to give 10 (15.0 mg).
Amarantholidol A glycoside (6): Colorless oil; [α]25D: -17.3° (c 0.85, MeOH); UV λmax (MeOH) nm (log ε): 200 (4.04); IR (neat) νmax cm-1: 3397 (OH), 1642 (C=C); HRESIMS m/z : 457.2426 [M+Na]+, (calc. for C21H38O9Na: 457.2408); 1H-NMR (CD3OD, 500 MHz): see Table 1; 13C-NMR (CD3OD, 125 MHz): δ 112.2 (C-1), 146.5 (C-2), 74.2 (C-3), 48.4 (C-4), 71.6 (C-5), 126.4 (C-6), 141.8 (C-7), 37.9 (C-8), 30.5 (C-9), 79.0 (C-10), 73.9 (C-11), 26.0 (C-12), 25.0 (C-13), 17.2 (C-14), 28.7 (C-15), 100.2 (C-1’), 75.3 (C-2’), 78.3 (C-3’), 72.0 (C-4’), 78.2 (C-5’), 63.1(C-6’).
Amarantholidoside II (7): Colorless oil; [α]25D: -49.9° (c 0.30, MeOH); FABMS m/z : 439 [M+Na]+; 1H-NMR (CD3OD, 500 MHz): see Table 1; 13C-NMR (CD3OD, 125 MHz) : δ 112.1 (C-1), 146.5 (C-2), 74.1 (C-3), 48.4 (C-4), 71.5 (C-5), 126.5 (C-6), 141.5 (C-7), 36.8 (C-8), 34.2 (C-9), 76.1 (C-10), 149.0 (C-11), 111.6 (C-12), 17.9 (C-13), 17.0 (C-14), 28.7 (C-15), 100.2 (C-1’), 75.2 (C-2’), 78.3 (C-3’), 72.0 (C-4’), 78.3 (C-5’), 63.1 (C-6’).
Table 1. 1H-NMR (500 MHz, CD3OD) spectral data of 6, 6a and 7.
Table 1. 1H-NMR (500 MHz, CD3OD) spectral data of 6, 6a and 7.
Position66a7
1a5.26 (dd, J = 16.5, 2.0 Hz)5.33 (dd, J = 16.5, 2.0 Hz)5.25 (dd, J = 17.5, 2.0 Hz)
1b5.03 (dd, J = 10.5, 2.0 Hz)5.12 (dd, J = 10.5, 2.0 Hz)5.03 (dd, J = 10.5, 2.0 Hz)
25.98 (dd, J = 16.5, 10.5 Hz)5.98 (dd, J = 16.5, 10.5 Hz)5.98 (dd, J = 17.5, 10.5 Hz)
4a1.99 (dd, J = 14.5, 8.0 Hz)1.77 (dd, J = 14.5, 8.0 Hz)1.98 (dd, J = 14.5, 8.0 Hz)
4b1.66 (dd, J = 14.5, 4.0 Hz)1.58 (dd, J = 14.5, 4.0 Hz)1.64 (dd, J = 14.5, 4.0 Hz)
54.92 (ddd, J = 10.0, 8.0, 4.0 Hz)4.62 (ddd, J = 10.0, 8.0, 4.0 Hz)4.91 (ddd, J = 10.5, 8.0, 4.0 Hz)
65.16 (d, J = 10.0 Hz)5.16 (d, J = 10.0 Hz)5.14 (dd, J = 10.5, 2.0 Hz)
8a2.30 (ddd, J = 13.5, 10.0, 5.0 Hz)2.25 (ddd, J = 13.5, 10.0, 5.0 Hz)1.68 (m)
8b2.11 (ddd, J = 13.5, 9.0, 8.0 Hz)2.03 (ddd, J = 13.5, 9.0, 8.0 Hz)
9a1.76 (m)1.76 (m)2.08 (m)
9b1.41 (m)1.41 (m)
103.24 (dd, J = 10.5, 2.0 Hz)3.22 (dd, J = 10.5, 2.0 Hz)4.01 (t, J = 7.0 Hz)
121.18 (3H, s)1.18 (3H, s)4.94 (s, H-12a)
4.80 (s, H-12b)
131.15 (3H, s)1.15 (3H, s)1.73 (3H, s)
141.71 (3H, s)1.67 (3H, s)1.70 (3H, s)
151.30 (3H, s)1.26 (3H, s)1.30 (3H, s)
1'4.25 (d, J = 8.0 Hz) 4.23 (d, J = 8.0 Hz)
2'3.18 (m) 3.17 (m)
3'3.28 (m) 3.29 (m)
4'3.28 (m) 3.29 (m)
5'3.18 (m) 3.17 (m)
6'a3.87 (dd, J = 11.5, 2.0 Hz) 3.87 (dd, J = 11.5, 2.5 Hz)
6'b3.67 (dd, J = 11.5, 6.0 Hz) 3.68 (dd, J =11.5, 6.0 Hz)

Enzymatic hydrolysis of 6

Compound 6 (3.0 mg) in distilled water (3.0 mL) was stirred with β-glucosidase (8.0 mg, TCI Co., Japan) in a sealed tube at room temperature for 7 days [2,14]. The reaction mixture was suspended with CHCl3 (15 mL) and the CHCl3 layer was evaporated in vacuo. The CHCl3 extract (1.7 mg) was purified using RP-C18 HPLC (MeOH - H2O = 50:50) to afford aglycone 6a (1.0 mg) as a colorless oil, [α]25D: +20.0° (c 0.05, MeOH), 1H-NMR (CD3OD, 500 MHz): see Table 1. The sugar in the distilled water layer was identified as D-glucose by co-TLC (EtOAc – MeOH - H2O = 9:3:1, Rf value: 0.17) with a D-glucose standard (Aldrich Co., USA).

Acknowledgments

This research was supported by the Korea Science and Engineering Foundation (KRF-2004-202- E00227). The authors would like to thank Dr. Eun Kyung Kwon, Sung Im Lee and Dr. Jung Ju Seo at the Korea Basic Science Institute for the measurements of NMR and MS spectra.

References

  1. Choi, S. Z.; Choi, S. U.; Lee, K. R. Cytotoxic sesquiterpene lactones from Saussurea calcicola. Arch. Pharm. Res. 2005, 28, 1142–1146. [Google Scholar] [CrossRef]
  2. Lee, S. O.; Choi, S. Z.; Choi, S. U.; Lee, K. C.; Chin, Y. W.; Kim, J. W.; Kim, Y. C.; Lee, K. R. Labdane diterpenes from Aster spathulifolius and their cytotoxic effects on human cancer cell lines. J. Nat. Prod. 2005, 68, 1471–1474. [Google Scholar] [CrossRef]
  3. Song, J. T. The sauras of Korean resources plants; Ilheung: Seoul, 1989; p. 346. [Google Scholar]
  4. Nakatani, N.; Kayano, S.; Kikuzaki, H.; Sumino, K.; Katagiri, K.; Mitani, T. Identification, quantitative determination, and antioxidative activities of chlorogenic acid isomers in prune (Prunus domestica L.). J. Agric. Food Chem. 2000, 48, 5512–5516. [Google Scholar]
  5. Flamini, G.; Antognoli, E.; Morelli, I. Two flavonoids and other compounds from the aerial parts of Centaurea bracteata from Italy. Phytochemistry 2001, 57, 559–564. [Google Scholar]
  6. Peng, L. Y.; Shuang, X. M.; Bei, J.; Hong, Z.; Han, D. S. Constituents from Lonicera japonica. Fitotetapia 2000, 71, 713–715. [Google Scholar]
  7. Cho, J. Y.; Moon, J. H.; Seong, K. Y.; Park, K. H. Antimicrobial activity of 4-hydroxybenzoic acid and trans 4-hydroxycinnamic acid isolated and identified from rice hull. Biosci. Biotechnol. Biochem. 1998, 62, 2273–2276. [Google Scholar]
  8. Greca, M. D.; Ferrara, M.; Fiorentino, A.; Monaco, P.; Previtera, L. Antialgal compounds from Zantedeschia aethiopica. Phytochemistry 1998, 49, 1299–1304. [Google Scholar]
  9. D'Abrosca, B.; Maria, P. D.; DellaGreca, M. D.; Fiorentino, A.; Golino, A.; Izzo, A.; Monaco, P. Amarantholidols and amarantholidosides: new nerolidol derivatives from the weed Amaranthus retroflexus. Tetrahedron 2006, 62, 640–646. [Google Scholar] [CrossRef]
  10. Lee, K. H.; Choi, S. U.; Lee, K. R. Sesquiterpenes from Syneilesis palmata and their cytotoxicity against human cancer cell lines in vitro. Arch Pham Res. 2005, 28, 280–284. [Google Scholar] [CrossRef]
  11. Nunez-Alarcon, J.; Rodriguez, E.; Schmid, R. D.; Mabry, T. J. 5-O-xylosylglucosides of apigenin and luteolin 7 - and 7, 4'- methyl ethers from Ovidia pillo - pillo. Phytochemistry 1973, 12, 1451–1454. [Google Scholar] [CrossRef]
  12. Zahir, A.; Jossang, A.; Bodo, B.; Provost, J.; Cosson, J. P.; Sevenet, T. Five new flavon 5-O-glycosides from Lethedon tannaensis: Lethedosides and Lethediosides. J. Nat. Prod. 1999, 62, 241–243. [Google Scholar] [CrossRef]
  13. Vignon, M. R.; Vottero, J. A. Nmr 13C., sur l’utilidation des esters pour l’attribution des carbones des molecules glucidioues. Tetrahedron Lett. 1976, 28, 2445–2448. [Google Scholar] [CrossRef]
  14. Fiorentino, A.; DellaGreca, M.; D'Abrosca, B.; Golino, A.; Pacifico, S.; Izzo, A.; Monaco, P. Unusual sesquiterpene glucosides from Amaranthus retroflexus. Tetrahedron 2006, 62, 8952–8958. [Google Scholar]
  • Sample Availability: Milligram quantities of compounds 1-5 and 8-10 are available from the authors.

Share and Cite

MDPI and ACS Style

Yang, M.C.; Kim, S.M.; Lee, K.H.; Kim, K.H.; Lee, K.R. A New Sesquiterpene Glycoside from the Aerial Parts of Saussurea triangulata. Molecules 2007, 12, 2270-2276. https://doi.org/10.3390/12102270

AMA Style

Yang MC, Kim SM, Lee KH, Kim KH, Lee KR. A New Sesquiterpene Glycoside from the Aerial Parts of Saussurea triangulata. Molecules. 2007; 12(10):2270-2276. https://doi.org/10.3390/12102270

Chicago/Turabian Style

Yang, Min Cheol, Sung Min Kim, Kyu Ha Lee, Ki Hyun Kim, and Kang Ro Lee. 2007. "A New Sesquiterpene Glycoside from the Aerial Parts of Saussurea triangulata" Molecules 12, no. 10: 2270-2276. https://doi.org/10.3390/12102270

Article Metrics

Back to TopTop