Three new acylated triterpene saponins from Acanthophyllum squarrosum

Three new triterpenoid saponins, 1-3, were isolated from the roots of Acanthophyllum squarrosum. Their structures were established mainly by 2D NMR techniques as 3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucuronopyranosyl-gypsogenin-28-O-beta-D-xylopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-beta-D-xylopyranosyl-(1-->4)-3-O-acetyl-alpha-L-rhamnopyranosyl-(1-->2)-3,4-di-O-acetyl-beta-D-fucopyranoside (1), 3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucuronopyranosyl-gypsogenin-28-O-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-[5-O-acetyl-alpha-L-arabinofuranosyl-(1-->3)]-4-O-acetyl-beta-D-fucopyranoside (2), and 3-O-beta-D-glucopyranosyl-quillaic acid-28-O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->6)]-beta-D-glucopyranoside (3).     

Characterization of new sweet triterpene saponins from Albizia myriophylla

Five new oleanane-type triterpene saponins, albiziasaponins A-E (1-5), were isolated from the stems of Albizia myriophylla collected in Thailand, together with two known triterpene saponins, licorice-saponin F3 and yunganoside B(1). The structures of the new compounds were elucidated on the basis of chemical and physicochemical evidence. In addition, when sensory tests were performed on sweetness, albiziasaponin B (2), with a carbonyl group at the C-30 position, was found to show a potent sweetness intensity relative to sucrose (600 times).     

Two new biologically active triterpene saponins from Acanthophyllum squarrosum

Two novel triterpenoid saponins (1 and 2) have been isolated from the roots of Acanthophyllum squarrosum. The structures were established mainly by a combination of 2D NMR techniques as 3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-be ta-D-glucuronopyranosylgypsogenin-28-O-beta-D-xylopyranosyl-(1-->3 )-b eta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->4)-[alpha-L- rhamnopyranosyl-(1-->3)]-beta-D-fucopyranoside (1) and 3-O-beta-D-glucopyranosylgypsogenin-28-O-alpha-L-rhamnopyranosyl-( 1-- >2)-alpha-L-arabinopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->6 )]- beta-D-glucopyranoside (2). Compound 1 showed a moderate concentration-dependent immunomodulatory effect in an in vitro lymphocyte proliferation assay.     

Junceosides A-C, new triterpene saponins from Arenaria juncea.

Three novel triterpenoid saponins, junceosides A (1), B (2), and C (3), together with two known saponins have been isolated from the roots of Arenaria juncea. Their structures were elucidated using a combination of homo- and heteronuclear 2D NMR techniques (COSY, TOCSY, NOESY, HSQC, and HMBC) and by FABMS. The new compounds were characterized as 3-O-alpha-L-arabinopyranosyl-(1-->2)-[beta-D-galactopyranosyl-(1-->3)]-beta-D-glucuronopyranosylgypsogenin-28-O-beta-D-glucopyranosyl(1-->3)-[beta-D-xylopyranosyl-(1-->4)]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside (1), 3-O-alpha-L-arabinopyranosyl-(1-->2)-[beta-D-galactopyranosyl-(1-->3)]-beta-D-glucuronopyranosylgypsogenin-28-O-beta-D-xylopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside (2), and 3-O-beta-D-xylopyranosyl-(1-->3)-[beta-D-galactopyranosyl-(1-->2)]-beta-D-glucuronopyranosylgypsogenin-28-O-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside (3).     

Five new triterpene saponins from Pulsatilla patens var. multifida

Five new oleanane-type glycosides (1-5), along with two known triterpene saponins, were isolated from the roots of Pulsatilla patens var. multifida (Ranunculaceae). The structures of the new triterpene saponins were elucidated as 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-galactopyranosyl hederagenin 28-O-beta-D-glucopyranosyl ester (1), hederagenin 3-O-[beta-D-glucopyranosyl(1-->2)][beta-D-glucopyranosyl(1-->6)]-beta -D-galactopyranoside (2), 3-O-beta-D-glucopyranosyl bayogenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (3), 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-galactopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (4), and 3-O-[beta-D-glucopyranosyl(1-->2)][beta-D-glucopyranosyl(1-->6)]-beta -D-galactopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester (5). Structure elucidation was accomplished by 1D and 2D NMR (HMQC, HMBC, and ROESY) methods, FABMS, and hydrolysis.     

Eranthisaponins A and B,two new bisdesmosidic triterpene saponins from the tubers of Eranthis cilicica

The present investigation aimed at the glycoside constituents of the tubers of Eranthis cilicica has resulted in the isolation of two new bisdesmosidic triterpene saponins based upon hederagenin, named eranthisaponins A (1) and B (2), along with four known triterpene saponins. The structures of the new saponins 1 and 2 were determined on the basis of spectroscopic analysis, including extensive 1D and 2D NMR data, and acid hydrolysis followed by chromatographic analysis. This is the first report concerning the secondary metabolites of E. cilicica.     

Effects of triterpene saponins from Astragalus species on in vitro cytokine release

Roots of Astragalus species are used to treat leukemia and for wound healing in Turkish folk medicine. In order to evaluate this information, the effect of 13 cycloartane- and 1 oleanan-type triterpene saponins isolated from Turkish species (Astragalus brachypterus, Astragalus cephalotes, Astragalus microcephalus, and Astragalus trojanus), as well as methanol extracts from the roots of three Astragalus species (Astragalus cephalotes, Astragalus oleifolius and Astragalus trojanus) were studied. Cytokine concentrations of interleukins IL-1beta, IL-8 and TNF-alpha after bacterial lipopolysaccharide (LPS) and IL-2, IL-4 and INF-gamma after phorbolacetate (PHA) stimulation were determined using commercial enzyme-linked immunosorbent assay (ELISA) kits. All triterpene saponins tested in the present study showed a prominent IL-2 inducing activity between 35.9% and 139.6%. Among the extracts the highest score was obtained for Astragalus oleifolius (141.2%). Glycosides of 20,24-epoxy and 20,25-epoxy cycloartanes showed higher IL-2 inducing activity than those of acyclic-cycloartane derivatives as well as aglycone of 20,24-epoxy cycloartanes, cycloastrogenol. Especially the activity of Astragaloside VII, a tridesmosidic glycoside of cycloastrogenol, was the most remarkable. The oleanan-type triterpene saponin also showed a prominent IL-2 inducing activity. IL-2 is a cytokine produced by activated T cells, which has shown powerful immunostimulatory and antineoplastic properties. Accordingly, the IL-2 inducing activity of the triterpene saponins might be the mechanism involved in order to explain the immunomodulatory and anticancer effects of Astragalus species.     

Antiproliferative triterpene saponins from Entada africana

Nine new ester saponins (1-9) were isolated from the roots of Entada africana. Their structures were elucidated by 1D and 2D NMR experiments including 1D and 2D TOCSY, DQF-COSY, HSQC, and HMBC spectroscopy, as well as ESIMS analysis, and chemical methods. The aglycon moieties were found to be echinocystic acid for compounds 1, 2, 4-6, 8, and 9 and acacic acid for 3 and 7. All isolated compounds were tested for their antiproliferative activity against the J774.A1, HEK-293, and WEHI-164 cell lines. Moderate to high cytotoxic potency was found for almost all compounds tested.     

Antiproliferative triterpene saponins from Trevesia palmata

During the course of a study of plants of the family Araliaceae, antiproliferative activity was demonstrated by the crude saponin fraction of Trevesia palmata. After chromatographic purification, six new bisdesmosidic saponins (1-6), along with two known triterpenoid saponins, (7 and 8), were isolated. The structures of 1-6 were determined by (1)H-(1)H correlation spectroscopy (COSY-DQF, 1D TOCSY, 2D HOHAHA, 1D ROESY) and (1)H-(13)C (HSQC, HMBC) spectroscopy. The antiproliferative activity of compounds 1-8 and of their prosapogenins (2a-7a) prepared by alkaline hydrolysis, was evaluated using three continuous culture cell lines.     

Dammarane-type triterpene saponins from Panax japonicus

Six new dammarane-type saponins (1-6), together with 11 known saponins (7-17), were isolated from Ye-Sanchi, the underground part of Panax japonicus collected in the South of Yunnan Province, China. Their structures were elucidated by chemical and spectroscopic means.     

Three new triterpenoid saponins from Aralia echinocaulis

Objective: To study the active ingredients in the root bark of Aralia echinocaulis. Methods: Three triterpenoid saponins were separated from the 70% ethanol extracts and purified by column chromatography and their structures were determined by spectroscopic analysis. Compound 1 and 3 were evaluated for antioxidant activity by the in vitro DPPH free radical scavenging ability and the protective effect of OH- induced DNA oxidative damage. Results: Compound 1 was a new type of triterpenoid saponin, named as echinocaulisaglycone 3-O-β-D-glucopyranoside (echinocaulisaponin A), and it had good antioxidant activity. Compound 2 was similar to compound 1, named as 1-hydroxyl-echinocaulisaglycone 3-O-β-D-glucopyranoside (echinocaulisaponin B). Compound 3 was also a new type of triterpenoid saponin, named as echinocaulisaglycone II 3-O-α-L-arabinopyranosyl-(1”→4’)-β-D-glucopyranosiduronic acid (echinocaulisaponin C), and its antioxidant activity was weaker than compound 1. Conclusion: In this study, three new compounds were discovered and two of them were carried out in vitro anti-oxidation studies, laying the foundation for further research on the treatment of related diseases (cardiovascular disease, arthritis, age-related macular degeneration, etc.) through anti-oxidation or quenching free radical function.     

Cytotoxic cycloartane triterpene saponins from Actaea asiatica

Three new 9,19-cycloartane triterpene glycosides, asiaticoside A (1), asiaticoside B (2), and 25-O-ethylcimigenol-3-O-beta-D-xylopyranoside (3), together with cimiacemoside I (4), 25-O-acetylcimigenol-3-beta-O-D-xyloside (5), and 25-anhydrocimigenol-beta-O-D-xyloside (6) were isolated from the roots/rhizomes extract of Actaea asiatica, and their structures were established by spectroscopic methods (IR, HRESIMS, and NMR). Compounds 1-3, 5, and 6 had notable cytotoxicity against HepG2 and MCF-7 cancer cell lines.     

Chionaeosides A-D, triterpene saponins from Paronychia chionaea

Four new triterpenoid saponins, chionaeosides A-D (1-4) were isolated from the roots of Paronychia chionaea. On the basis of their spectroscopic data, the structures of the new saponins were established as 3-O-alpha-L-arabinopyranosylgypsogenic acid 28-O-beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (1), 3-O-alpha-L-arabinopyranosylgypsogenic acid 28-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (2), 3-O-alpha-L-arabinopyranosylgypsogenic acid 28-O-beta-D-glucopyranoside (3), and 3-O-alpha-L-arabinopyranosylgypsogenic acid (4).     

Pursaethosides A-E, triterpene saponins from Entada pursaetha

Five new triterpenoid saponins, pursaethosides A-E (1-5), were isolated from the n-BuOH extract of the seed kernels of Entada pursaetha along with the known phaseoloidin. The structures of 1-5 were elucidated mainly by spectroscopic data interpretation and chemical degradation. Pursaethosides C-E (3-5) possess as a common structural feature entagenic acid as aglycon, which is rare among triterpene saponins. Compounds 2-4 and phaesolidin were found to be not cytotoxic when tested against HCT 116 and HT-29 human colon cancer cells.     

Glandulosides A-D, triterpene saponins from Acanthophyllum glandulosum

Four novel triterpenoid saponins, glandulosides A (1), B (2), C (3), and D (4), together with two known saponins (5 and 6) have been isolated from the roots of Acanthophyllum glandulosum. Their structures were elucidated using a combination of homo- and heteronuclear 2D NMR techniques (COSY, TOCSY, NOESY, HSQC, and HMBC) and by FABMS. The new compounds were characterized as 23-O-beta-D-galactopyranosylgypsogenic acid-28-O-beta-D-glucopyranosyl-(1-->3)-[beta-d-galactopyranosyl-(1-->6)]-beta-D-galactopyranoside (1), 3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucuronopyranosylgypsogenin-28-O-beta-D-xylopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-l-rhamnopyranosyl-(1-->2)-3-O-acetyl-beta-D-fucopyranoside (2), 3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucuronopyranosylgypsogenin-28-O-beta-D-xylopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-3,4-di-O-acetyl-beta-D-fucopyranoside (3), and 3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucuronopyranosylgypsogenin-28-O-beta-D-xylopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-l-rhamnopyranosyl-(1-->2)-[3-O-acetyl-beta-D-quinovopyranosyl-(1-->4)]-beta-D-fucopyranoside (4).     

Cycloartane triterpene saponins from the roots of Cimicifuga foetida

The structures of two new cycloartane-type saponin constituents of the roots of Cimicifuga foetida were established by the interpretation of spectroscopic data as 2'-O-acetylactein (1) and 2'-O-acetyl-27-deoxyactein (2), respectively. Also isolated were the known compounds actein, 27-deoxyactein, cimicifugoside H-1, and 15alpha-hydroxycimicidol 3-O-beta-D-xyloside.     

Antitumor activities of dammarane triterpene saponins from Bacopa monniera

Bioassay‐guided methods were used to test the antitumor activity of methanol extract of the whole plant of Bacopa monniera (L.) Wettst. and four different fractions (petroleum ether, CHCl₃, EtOAc, and n‐BuOH fractions) of the methanol extract. Among the five crude samples, n‐BuOH fraction was noted to have the highest antitumor activity. The dammarane triterpene saponins isolated from n‐BuOH fraction, bacopaside É (1) and bacopaside VII (3), had potential antitumor effect. 1 and 3 showed cytotoxicity of all the tested human tumor cell lines MDA‐MB‐231, SHG‐44, HCT‐8, A‐549 and PC‐3M in MTT assay in vitro, and showed 90.52 % and 84.13 % inhibition in mouse implanted with sarcoma S180 in vivo at the concentration of 50 μmol/kg, respectively. The remaining two compounds, bacopaside II (2) and bacopasaponin C (4) were found to be much less potent compared with 1 and 3. 1 and 3 significantly inhibited human breast cancer cell line MDA‐MB‐231 adhesion, migration and Matrigel invasion in vitro at the concentration of 50 μmol/L. Since no antitumor activities about the monomers from Bacopa monniera (L.) Wettst. have been reported, these results indicate that the mechanism of action of 1 and 3 needs further study. Copyright © 2009 John Wiley & Sons, Ltd.     

Bioactive triterpene saponins from the roots of Phytolacca americana

Five new triterpene saponins named phytolaccasaponins N-1 (1), N-2 (2), N-3 (3) N-4 (4), and N-5 (5) were isolated from the roots of Phytolacca americana together with seven known triterpene saponins (6-12). The structures of the five new saponins were established as shown in structures 1-5 on the basis of their spectroscopic data. The MDR-reversal activity of 1-12 was evaluated on the basis of the amount of calcein accumulated in MDR human ovarian cancer 2780 AD cells in the presence of each compound. The most effective compound was 8 (155% of control at 25 microg/mL).     

Cytotoxic acylated triterpene saponins from the husks of Xanthoceras sorbifolia

Four new oleanane-type triterpene saponins, xanifolia-Y0 (1), xanifolia-Y2 (2), xanifolia-Y3 (3), and xanifolia-Y7 (4), were isolated from the husks of Xanthoceras sorbifolia along with two known analogues, xanifolia-Y8 (5) and xanifolia-Y10 (6). The structures of 1-4 were determined by spectroscopic data interpretation and chemical degradation. Compounds 1-6 were evaluated for their cell-growth inhibition activity toward human ovarian cancer cells (OVCAR3) by a MTT assay, and the IC50 values ranged from 4 to 13 microM. On the basis of the results obtained, it is concluded that a C-3 trisaccharide with a galactose and acylation with an angeloyl group at both C-21 and C-22 are important for cell inhibition activity for this class of compounds.     

New bisdesmosidic triterpene saponins from the roots of Pulsatilla chinensis

Further phytochemical analysis aimed at the triterpene saponin constituents of the roots of Pulsatilla chinensis has resulted in the isolation of four new bisdesmosidic triterpene saponins whose aglycons are based on the lupane skeleton (1-4), together with three known saponins (5-7). The structures of the new compounds were determined by spectroscopic analysis and acid-catalyzed hydrolysis.