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Two new triterpenes mayteneri A ( 1 ), mayteneri B ( 2 ), and seven known compounds ( 3-9 ) were isolated from stems of Maytenus hookeri Loes. The chemical structures of compounds 1 and 2 were established by 1D, 2D NMR, HRESIMS analysis, and calculating electronic circular dichroism (ECD). The structures of known compounds 3 - 9 were determined by comparison of their spectral with those reported. Compounds 4 - 7 showed significant inhibitory activity for NLRP3 inflammasome, with the IC 50 values of 2.36-3.44  μ M.

A new flavonolignan, sonyamandin (1) , along with other known compounds was isolated from the aerial parts and seeds extracts of Silybum marianum (milk thistle) collected from Jordan. The known ones are ursolic acid (2) , oleanolic acid (3) , maslinic acid (4), oleic acid (5) , β-sitosterol (6) , β-, sitosteryl glucoside (7), apigenin (8) , kaempferol-3-O-rhamnoside (9) , apigenin-7-O-β-D-glycoside (10) , isosylibin A (11) , isosylibin B (12), and silybin B (13) . The absolute stereochemistry of 1 was confirmed by 2D NMR and CD analysis.

Glycosylation is an effective approach to improve the druggability of natural products by increasing their water solubility. In this work, we report the glycosylation of oleanane-type triterpenoids by a recombinant microbial glycosyltransferase YjiC1. A preliminary screening test indicated YjiC1 exhibited robust capabilities for O-glycosylation of triterpenoids, based on LC/MS analysis. Among the products, two new compounds (2a and 3a), together with a known one (1a), were isolated and characterized. These products exhibited improved water solubility, and 3a showed moderate anti-HIV activities at 100 μM. This reaction provides a facile and efficient approach to synthesize the glucosides of triterpenoids.

Over the past decades, a number of phytochemicals have been reported to possess potent pharmacological effects. Saikosaponins represent a group of oleanane derivatives, usually as glucosides, which are commonly found in medicinal plants Bupleurum spp., which have been used as traditional Chinese medicine for more than 1,000 years in China. Emerging evidence suggests that saikosaponins have many pharmacological effects, including sedation, anticonvulsant, antipyretic, antiviral, immunity, anti-inflammation, antitumor properties, protecting liver and kidney and so on. The present review provides a comprehensive summary and analysis of the pharmacological properties of saikosaponins, supporting the potential uses of saikosaponins as a medicinal agent.

Ten novel oleanolic acid (OA) derivatives were synthesized through modifications at positions of A ring and C-28. Inhibitory activities of the oleanolic acid derivatives against SGC7901 and A549 cell lines were evaluated and confirmed by the tetrazolium bromidesalt (MTT) assay. The lab results revealed that all these compounds displayed some antitumor activity against SGC-7901 and A-549 cell lines. Among them, II 4 and II 5 exhibited excellent antitumor activities against SGC7901 cells and A549 cells, compared with gefitinib. Molecular docking studies have shown that compounds II 4 and II 5 produce potent antitumor activities by interacting with C-kit receptor through hydrogen bonds and hydrophobic bonds.

The pentacyclic triterpenoid hederagenin (1) was subjected to biotransformation by Cunninghamella echinulate CGMCC 3.2000, Mucor subtilissimus CGMCC 3.2454 and Pseudomonas oleovorans CGMCC 1.1641. Three metabolites were obtained. On the basis of nuclear magnetic resonance and high-resolution mass spectral analyses, their structures were characterized as 3β, 23-dihydroxyolean-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (2), 3β, 15α, 23-trihydroxyolean-12-en-28-oic acid (3), 1β, 3β, 23-trihydroxyolean-12-en-28-oic acid (4), and metabolite (3) was a new compound. This was the first report on the biotransformation of hederagenin.

Two new triterpene saponins, clinopodiside VI (1) and saikosaponin c (2), along with six known saikosaponins (3-8), were isolated from the plant of Clinopodium polycephalum. Compounds 1-3 showed moderate inhibition against H9c2 cell damage induced by H 2 O 2 .

An efficient route for the semi-synthesis of either 1α- or 1β-OH epimers of 1-hydroxy-3-deoxyolean-12-en-28-oic acid (1), 6-8 steps from oleanolic acid is reported. The synthesis involves stereoselective formation of α,β-unsaturated epoxy ketone and subsequent Wharton reaction as key steps, offering a new access to the 1-O-substituted oleanolic acid-type pentacyclic triterpenoids.

Two new isoxazoline compounds, 1-oxa-2-azaspiro[4.5]dec-2-ene-8β-ol (1) and 1-oxa-2-azaspiro[4.5]dec-2-ene-8α-ol (2), were isolated from the husks of fruits of Xanthoceras sorbifolia Bunge and their structures were determined by spectroscopic analyses, including X-ray crystallography, HRESI-MS, UV, IR, and 1D and 2D NMR (HSQC, HMBC, NOESY) methods. Neither compound showed significant inhibitory effects on butyrylcholinesterase (BuchE) and acetylcholinesterase (AChE), nor the selected tumor cells growth. Based on an online activity prediction program (PASS ONLINE), the structures with isoxazoline skeletons were found to show potential anti-asthmatic (AM) and anti-anaphylaxis (AP) activities; moreover, compounds 1 and 2 were predicted to possess high affinities for many enzymes involved in AM and AP according to the RCSB Protein Data Bank. High-affinity binding to phosphodiesterase IV (PDE-4), an important inflammatory modulator in asthma, was demonstrated experimentally, beside that, the predicted structures based on compounds 1 and 2 were analyzed for PDE-4 interactions using the molecular docking methodology of Discovery Studio 3.0 (DS 3.0). The predicted structure 2A-6 exhibited much higher affinity and stability of PDE-4 binding than the clinical PDE-4 inhibitor rolipram.

Two new 28-nor-oleanane-type triterpene saponins, oleiferoside U (1), and oleiferoside V (2) were isolated from the 50% EtOH extract of the roots of Camellia oleifera C. Abel. Their structures were elucidated as camellenodiol 3β-O-β-d-galactopyranosyl-(1→2)-β-d-xylopyranosyl-(1→2)-[β-d-galactopyranosyl-(1→3)]-β-d-glucuronopyranoside and camellenodiol 3β-O-β-d-galactopyranosyl-(1→3)-β-d-xylopyranosyl-(1→2)-[β-d-galactopyranosyl-(1→3)]-β-d-glucuronopyranoside. Their chemical structures were established mainly on the basis of integrated spectroscopic techniques. In vitro, cytotoxic activities of the two new triterpene saponins were evaluated against three human tumor cell lines (A549, SMMC-7721, and MCF-7) using the MTT assay. Both of them showed a certain cytotoxic activities toward the tested cell lines and gave IC50 values in the range of 45.04-63.22 μM.

From the leaves of Schefflera sessiliflora De P. V., two new triterpene saponins including one oleanane-type saponin, named scheffleraside C (1) and one lupane-type saponin scheffleraside D (2), together with six known triterpene saponins (3-8), were isolated by various chromatography methods. Among them, 3 was found for the first time from natural sources, while 6-8 were isolated for the first time from the genus Schefflera. Their structures were elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments, and comparison of their NMR data with previously reported data. Their α-glucosidase inhibition and cytotoxic activity against MCF-7 human breast cancer cell lines were evaluated. The isolates (1, 3-5, 8) showed stronger α-glucosidase inhibitory activity (IC50 = 5.99-76.58 μM) than the standard drug acarbose (IC50 = 214.50 μM). At the concentration of 100 μg/ml, the isolates (1, 2) showed appreciable cytotoxic activity (67.92, 63.83%, respectively).

Phytochemical study on the aerial parts of Anemone taipaiensis for the first time led to the isolation of two new oleanane-type triterpenoid saponins 1 and 2, together with four known saponins (3-6). Their structures were elucidated by extensive spectroscopic analysis and chemical evidences. Saponins 2-4 exhibited cytotoxicity against human glioblastoma U251MG cell line with IC50 values ranging from 1.56 to 80.62 μM.

Two new triterpenoid saponins were isolated from the 70% ethanol extract of the rhizome of Anemone amurensis, they are oleanolic acid 28-O-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl ester (1) and 23,27-dihydroxy oleanolic acid 3-O-α-l-arabinopyranoside (2). The structures of 1 and 2 were elucidated on the basis of chemical and spectral analysis, including 1D and 2D NMR data and HR-ESI-MS. Compounds 1 and 2 were tested for cytotoxicities against three human cancer cell lines (A549, Hep-G2, and MCF-7). Compound 1 showed potent cytotoxicity with IC50 values of 34.76, 41.17, and 28.92 μM, respectively, while compound 2 with IC50>100 μM.

Three new saikosaponin analogs, comastomasaponins I-K (1-3), were isolated from the aerial portions of Comastomapedunculatum. The structures of these compounds were elucidated on the basis of spectroscopic data analysis, and their nitric oxide production inhibitory activity was evaluated invitro.

Two new triterpenoids, 2α,3β,16α,19α,23-pentahydroxyolean-12-en-28-oic acid (1) and 2α,3α,11α,21α,23-pentahydroxyurs-12-en-28-oic acid (2), were isolated from the aerial parts of Callicarpa kwangtungensis. Their structures were elucidated by 1D and 2D analyses, as well as MS and IR spectra.

Two new triterpenoids, 3β,6β-dihydroxy-12-oxo-13Hα-olean-28,19β-olide (1) and 3-oxo-olean-11,13(18)-dien-28,19β-olide (2) were isolated from the resin of Styrax tonkinensis (Pier.) Craib. The structures of both triterpenoids were determined by physicochemical and spectroscopic methods. Compound 1 is the second triterpene found with cis-fused C/D ring from the resin, which is rarely observed in oleanane-type triterpenes.

A new brominated polyunsaturated lipid, methyl (E,E)-14,14-dibromo-4,6,13-tetradecatrienoate (1), along with three known related analogues (2-4), were isolated from the Et2O-soluble portion of the acetone extract of Chinese marine sponge Xestospongia testudinaria treated with diazomethane. The structure of the new compound was elucidated by detailed spectroscopic analysis and by comparison with literature data. Compound 3 exhibited significant inhibitory activity against protein tyrosine phosphatase 1B (PTP1B), a key target for the treatment of type II diabetes and obesity, with an IC50 value of 5.30 ± 0.61 μM, when compared to the positive control oleanolic acid (IC50 = 2.39 ± 0.26 μM).

Compound 1, a triterpenoid saponin from Ardisia gigantifolia Stapf. showing potential anti-tumor activity, was transformed into three derivatives (2-4) by Aspergillus avenaceus 3.4454. Among them, compounds 2 and 3 are new compounds. Their structures were elucidated on the basis of 1D NMR, 2D NMR, HR-ESI-MS, and optical rotation data. Compounds 1-3 were evaluated for their cytotoxicity against human hepatocellular carcinoma and normal liver cells by cell counting kit 8 colorimetric assay. Compound 3 displayed better cytotoxicity against Bel-7402 and HepG2 cell lines and much weaker cytotoxicity against normal liver L02 cell than that of positive control (epirubicin hydrochloride).

A novel minor bisindole alkaloid, racemosin C (1), characterized by a naturally unprecedented 8-hydroxy-2,4,6-cyclooctatrienone ring fused with two indole systems, was isolated from the green alga Caulerpa racemosa, together with one known related metabolite, caulersin (2). The structure of 1 was elucidated on the basis of extensive spectroscopic analysis, and by comparison with the data of related known compounds. A plausible biosynthetic pathway of 1 was proposed. Compounds 1 and 2 exhibited significant PTP1B inhibitory activity with IC50 values of 5.86 ± 0.57 and 7.14 ± 1.00 μM, respectively, compared with the positive control oleanolic acid (IC50 = 3.03 ± 0.20 μM). On the basis of the data obtained, the Caulerpa bisindole alkaloids may be considered as a new class of PTP1B inhibitors.

Three new oleanane-type triterpene saponins, namely licorice-saponin M3 (1), licorice-saponin N4 (2), and licorice-saponin O4 (3), an artificial product (4), as well as five known triterpene glucuronides (5-9), were isolated from the roots of Glycyrrhiza glabra L. Their structures were established using 1D and 2D NMR spectroscopy, mass spectrometry, and by comparison with spectroscopic data reported in the literature. The inhibitory effects of the selected compounds on neuraminidase were evaluated, and the preliminary structure-activity relationship was also predicted.

Five new terpenoids including 2 labdane diterpenoids (1 and 2), 2 ent-kaurane diterpenoids (3 and 4), and a new oleanane triterpenoid (5), along with 13 known compounds (6-18), were isolated from the ethyl acetate fraction of 70% acetone extract of the rhizomes of Isodonadenantha. Their structures were elucidated based on the analyses of spectroscopic data and comparison of their physicochemical properties. The structure of 1 was further confirmed by single-crystal X-ray diffraction. Cytotoxicity and antibacterial activities of the samples were measured by MTT method and the filter paper disk agar diffusion method. But none of them showed significant activities.

Three new oleanane-type triterpenoid saponins named celosins H, I, and J were isolated from the seeds of Celosia argentea L. Their structures were characterized as 3-O-β-D-xylopyranosyl-(1 → 3)-β-D-glucuronopyranosyl-polygalagenin 28-O-β-D-glucopyranosyl ester, 3-O-β-D-glucuronopyranosyl-medicagenic acid 28-O-β-D-xylcopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 2)-β-D-fucopyranosyl ester, and 3-O-β-D-glucuronopyranosyl-medicagenic acid 28-O-α-L-arabinopyranosyl-(1 → 3)-[β-D-xylcopyranosyl-(1 → 4)]-α-L-rhamnopyranosyl-(1 → 2)-β-D-fucopyranosyl ester by NMR, MS, and chemical evidences, respectively. In our opinion, celosins H-J could be used as chemical markers for the quality control of C. argentea seeds.

Microbial transformation of the oleanolic acid (1) using Trichothecium roseum (pers.) Link (M 95.56) has resulted in the isolation of two new hydroxylated type metabolites, characterized as 15α-hydroxy-3-oxo-olean-12-en-28-oic acid (2) and 7β,15α-dihydroxy-3-oxo-olean-12-en-28-oic acid (3). The structure elucidation of these metabolites was based primarily on HR-EIMS, 1D NMR, and 2D NMR analyses.

A new compound 3-acetyloxy-epicycloeucalenol-24-one (1), with 11 known compounds 3α-acetyloxy-4α,14α-dimethyl-9β,19-cycloergost-24-oic acid (2), 3-epicycloeucalenol (3), 3-epicycloeucalenyl-24-one (4), 3-epicycloeucalenyl acetate (5), 4β,14α-dimethyl-5α-ergosta-9β,19-cyclo-24(31)-en-3β-hydroxy-4α-carboxylic acid (6), cycloeucalenone (7), friedelin (8), epifriedelanol (9), lup-20 (29)-en-3β,30-diol (10), betulin (11), lupeol (12), was isolated from the stems and leaves of Quercus variabilis Blume. Seven compounds (1-7) showed anti-inflammatory activity.

Two new oleanane-type triterpenoid saponins, kakkasaponin II (1) and kakkasaponin III (2), were isolated from the methanol extract of the flowers of Pueraria thomsonii (Leguminosae), together with seven known oleanane-type triterpenoid saponins, phaseoside IV (3), sophoradiol monoglucuronide (4), kakkasaponin I (5), kaikasaponin III (6), soyasaponin I (7), soyasaponin III (8), and soyasaponin IV (9). The structures of 1 and 2 were elucidated by spectroscopic methods including IR, ESI-TOF-MS, and 1D and 2D NMR experiments.

The cytotoxic activity of 36 saponins isolated from roots of Pulsatilla chinensis (Bunge) Regel against the human cancer cell lines (A549, SGC-7901) and the human hepatic cell line (HL-7702) was tested by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay. Saponins 1-14 showed considerable cytotoxic activity, whereas saponins 15-36 showed no significant activity, which suggested that a free carboxylic group located at C-28 of aglycon is essential for their cytotoxic activity. Moreover, the analysis of structure-activity relationships also suggested that the oleanane-type saponins showed better cytotoxic activity than lupane-type saponins, and the length and linkage of glycolic chain attached to C-3 of aglycon displayed an important effect to the potent cytotoxicity. In conclusion, oleanolic acid 3-O-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-α-l-arabinopyranoside (5) exhibited the most significant cytotoxic activity.

A new triterpenoid saponin, named 3-O-β-d-glucopyranosyl-(1 → 3)-β-d-xylopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 3)]-β-d-glucopyranosyl-(1 → 4)-[β-d-glucopyranosyl-(1 → 2)]-α-l-arabinopyranosyl-3β,16α,28,30-tetrahydroxy-olean-12-ene (1), along with four known triterpenoids (2-5), was isolated from the rhizomes of Ardisia gigantifolia. Their structures were elucidated by spectroscopic methods. Compounds 1-4 showed cytotoxic activity against Hela, EJ, BCG, and HepG-2 cell lines. The percentage of early apoptotic cells after treatment with 1 was significantly increased compared with control cells (p < 0.05).

A novel pyrrolidine alkaloid, (2R*,3S*,5S*)-N,2-dimethyl-3-hydroxy-5-(10-phenyldecyl)pyrrolidine (1), and 17 known compounds were isolated from Arisaema franchetianum Engl. (Araceae) tubers. The 17 compounds were bergenin (2), emodin (3), caffeic acid (4), nobiletin (5), 3-O-β-d-galactopyranosyl-hederagenin 28-O-β-d-xylopyranosyl(1 → 6)-β-d-galactopyranosyl ester (6), coniferin (7), qingyangshengenin (8), methylconiferin (9), syringaresinol 4'-O-β-d-glucopyranoside (10), gagaminine (11), perlolyrine (12), (S)-1-(1'-hydroxyethyl)-β-carboline (13), 1-(β-carboline-1-yl)-3,4,5-trihydroxy-1-pentanone (14), 1-methoxycarbonyl-β-carboline (15), indolo[2,3-α]carbazole (16), 4-hydroxycinnamic acid methyl ester (17), and methyl 4-[2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl)ethyl] ferulate (18). The inhibitory activities of compound 1 and its N-methyl derivative (1a) against porcine respiratory and reproductive syndrome virus (PRRSV), human leukemic K562 cells, and human breast cancer MCF-7 cells were evaluated. Compounds 1 [50% inhibited concentration (IC(50)) = 12.5 ± 0.6 μM] and 1a (IC(50) = 15.7 ± 0.9 μM) were cytotoxic against K562 cells. Compound 1a also had a weak effect on PRRSV with an IC(50) value of 31.9 ± 6.0 μM [selectivity index (SI) = 18.7].

Two new triterpenoid saponins (1, 2) and a known saponin (3) were isolated from the husks of Xanthoceras sorbifolia Bunge., and their structures were elucidated as 3-O-β-D-glucopyranosyl(1 → 6)-[angeloyl(1 → 2)]-β-D-glucopyranosyl-28-O-α-L-rhamnopyranosyl(1 → 2)-[β-D-glucopyranosyl(1 → 6)]-β-D-glucopyranosyl-21β,22α-dihydroxyl-olean-12-ene (1), 3-O-β-D-glucopyranosyl-28-O-[β-D-glucopyranosyl(1 → 2)]-β-D-glucopyranosyl-21β,22α-dihydroxyl-olean-12-ene (2), and 3-O-β-D-glucopyranosyl-28-O-[α-L-rhamnopyranosyl(1 → 2)]-β-D-glucopyranosyl-21β,22α-dihydroxyl-olean-12-ene (3), on the basis of the spectral analysis of NMR and chemical methods. Cytotoxic assay indicated that none of them showed obvious inhibitory effect on the proliferation of two human tumor cell lines.

Derivatives of oleanolic acid were synthesized and evaluated in vitro for their growth inhibition against human hepatocellular carcinoma cell line (HepG2) and colon cancer cell line (Col-02). Several derivatives exhibited moderate-to-good inhibitory activity, with 3 displaying the most promising inhibition [GI₅₀ = 1.75 μM (HepG2), 0.71 μM (Col-02)]. Structure-activity relationship analyses of these derivatives demonstrated that a 1-en-2-cyano-3-oxo in ring A and a nitro at C-17 were important in retention of the inhibition against HepG2 and Col-02 cells.

Two new phthalates bis(2-ethylundecyl)phthalate and bis(2-ethyltridecyl)phthalate have been isolated from the chloroform-soluble portion of the whole plant of Nepeta clarkei along with one known compound β-amyrin. The structures of the two new compounds and β-amyrin were assigned on the basis of their ¹H and ¹³C NMR spectra including 2D NMR techniques such as COSY, HMQC, and HMBC experiments and compared with the literature data.

Nine compounds were isolated from the leaves of Anthocephalus chinensis by column chromatography on silica gel and Sephadex LH-20, and their structures were elucidated by spectroscopic techniques as clethric acid-28-O-β-d-glucopyranosyl ester (1), mussaendoside T (2), β-stigmasterol (3), hederagenin (4), ursolic acid (5), clethric acid (6), 3β,6β,19α,24-tetrahydroxyurs-12-en-28-oic acid (7), mussaendoside I (8), and cadambine (9). Compounds 1 and 2, and 7 and 8 were isolated from the plants of this genus for the first time, and compounds 1 and 2 were new triterpenoid glycosides.

Two new triterpenoid saponins 1 and 2, along with six known saponins 3-8, were isolated from the roots of Dipsacus asper. The structures of new compounds were established as 3-O-β-d-glucopyranosyl-(1 → 4)-[α-l-rhamnopyranosyl-(1 → 3)]-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranosyl-hederagenin-28-O-β-d-glucopyranoside (dipsacus saponin J, 1) and 3-O-α-l-arabinopyranosyl-hederagenin-28-O-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranoside (dipsacus saponin K, 2). The structures were determined by extensive analysis of their spectroscopic data. Compounds 6 and 7 could significantly stimulate UMR106 cell proliferation and increase alkaline phosphatase activities in UMR106 cell at the concentration of 4 μM.

A new compound, 11-O-(3'-O-methylgalloyl)-bergenin (1), along with 11 known compounds (2-12), has been isolated from the rhizome of Astilbe chinensis. The chemical structure of compound 1 was determined by IR, MS, and NMR spectral data. All compounds were evaluated for the cytotoxic activity in vitro, and compound 4 showed a moderate cytotoxic activity against HepG2 cells.

Three new triterpenoid saponins, polygonoides C (1), D (2), and E (3), were obtained from the ethanolic extract of the rhizome of Polygonatum sibiricum Redoute. On the basis of NMR and ESI-MS spectra, and chemical evidence, the structures of the three new compounds were elucidated as 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-β-D-glucopyranosyl-3β,7β,22β-trihydroxy-oleanolic acid (1), 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-β-D-glucopyranosyl-3β,7β,22β-trihydroxy-oleanolic acid methyl ester (2), and 3-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-(1→4)-[α-L-rhamno-pyranosyl-(1→2)]-β-D-glucopyranosyl-3β,21β-dihydroxy-oleanolic acid 28-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-(1→3)-β-D-glucopyranoside (3).

Two new triterpenoid saponins (1 and 2) were isolated from the dried aerial parts of Dianthus superbus L. (Caryophyllaceae). Their structures were elucidated on the basis of spectral data to be 3-O-beta-D-glucopyranosyl olean-9(11),12-diene-23,28-dioic acid 28-O-beta-D-glucopyranoside (1) and 3-O-beta-D-glucopyranosyl olean-11,13(18)-diene-23,28-dioic acid 28-O-beta-D-glucopyranoside (2).

Two new oleane-type triterpene saponins, lysimachiagenoside E (1) and lysimachiagenoside F (2), were isolated from the aerial parts of Lysimachia foenum-graecum Hance. The structures were elucidated on the basis of 1D and 2D NMR techniques, including (1)H-(1)H COSY, HMQC, HMBC, TOCSY, ROESY experiments as well as chemical methods.

Two new triterpenoids taraxer-14-ene-1alpha,3beta-diol (1) and 3beta-hydroxytaraxer-14-ene-1-one (2), together with the known triterpenes taraxerol (3), betulin (4), betulinic acid (5), sumaresinolic acid (6), and 5-hydroxy-2-methoxy-1,4-naphthoquinone (7), 5,7-dihydroxy-6,8-dimethylchromone (8), alpha-monpalmitin (9), palmitic acid (10), 6beta-hydroxystigmast-4-en-3-one (11), beta-sitostero1 (12), have been isolated from the petroleum ether fraction of the ethanolic extract of Pterospermum heterophyllum. Their structures were established by spectroscopic methods including IR, MS, 1D, and 2D NMR experiments. Compounds 1-8 were evaluated against several human cancer cell lines. Compound 1 showed in vitro selective cytotoxicity against human lung cancer cell lines (A549) with an IC(50) value of 1.22 microM. Compound 7 showed significant cytotoxicity against the A549, HCT-8, Bel7402, BGC-823, and A2780 cancer cell lines with IC(50) values of 0.21, 0.55, 0.40, 0.59, and 0.34 microM, respectively. However, the other compounds were inactive (IC(50)>10 microM).

Two new oleanane-type triterpene saponins, lysimachiagenoside C (1) and lysimachiagenoside D (2), were isolated from the aerial parts of Lysimachia foenum-graecum Hance. The structures were elucidated on the basis of 1D and 2D NMR techniques, including (1)H-(1)H COSY, HMQC, HMBC, TOCSY, and ROESY experiments as well as chemical methods.

One new oleane-type triterpene saponin, named lysimachiagenoside A and the known 21-O-angeloylbarringtogenol C were isolated from the aerial parts of Lysimachia foenum-graecum Hance. 21-O-angeloylbarringtogenol C was a new natural product. These structures were identified on the basis of 1D- and 2D-NMR techniques, including 1H-1H COSY, HMQC, HMBC, TOCSY, and ROESY experiments as well as chemical methods.

Sixteen triterpenoid saponins (1-16) were isolated from the stems of Clematis parviloba, including a new compound, parvilobaside A (1), which was established as 23-O-acetyl-hederagenin-3-O-beta-D-ribopyranosyl-(1 --> 3)-alpha-L-rhamnopyranosyl-(1 --> 2)-alpha-l-arabinopyranoside on the basis of various spectroscopic techniques and chemical evidences. Among the isolated compounds, clematoside S (2) and alpha-hederin (4) showed moderate cytotoxic activities against four human tumor cell lines (HCT-8, Bel-7402, BGC-823, and A-2780) with IC(50) values in the range of 1.44-6.86 microg/ml.

Ardisiacrispin (A+B) is a mixture of ardisiacrispins A and B, derived from Ardisia crenata with a fixed proportion (2:1). The present study was conducted to investigate its anticancer activity on human cancer cells and its underlying mechanism of action. The (IC50)s of ardisiacrispin (A+B) on proliferation of several human cancer cell lines were in the range of 0.9-6.5 microg/ml by sulphorhodamine B-based colorimetric assay, in which Bel-7402 was the most sensitive cell line. Moreover, ardisiacrispin (A+B) induced dose-dependent apoptosis in Bel-7402 cells at doses of 1-10 microg/ml by flow cytometry, and resulted in the changes of the mitochondrial membrane depolarization, membrane permeability enhancement, and nuclear condensation in a dose-dependent manner through high-content screening analysis. Furthermore, ardisiacrispin (A+B) could disassemble microtubule in Bel-7402 cells; the fluorescence intensity of microtubules decreased at the concentration of 5-20 microg/ml. These findings suggest that ardisiacrispin (A+B) could inhibit the proliferation of Bel-7402 cells by inducing apoptosis and disassembling microtubule.

An efficient partial synthesis of 25-acetoxy-3alpha-hydroxyolean-12-en-28-oic acid (1), starting from oleanolic acid (2), has been developed in an efficient manner (13 steps, 21% yield), employing a photochemical reaction of nitrite 8 for the introduction of C-25 substituting group as the key step. Based on the comparison of its spectral data with those reported for compound 1 isolated from Liquidamber styraciflua, we found the structure in that paper was incorrectly assigned, and should be revised as 3alpha-acetoxy-25-hydroxyolean-12-en-28-oic acid (15).

Two new oleanane-type triterpenes, (23Z)-feruloylhederagenin (1) and (23E)-feruloylhederagenin (2), together with two known oleanane-type triterpenes, beta-amyrin acetate and beta-amyrin palmitate, have been isolated from the whole plant of Ludwigia octovalvis. The structures of 1 and 2 were characterised on the basis of spectral evidence.

A new triterpene glycoside, arjunetoside, together with oleanolic and arjunic acids has been isolated from the root bark of Terminalia arjuna. The structure of arjunetoside has been established as 3-O-beta-D-glucopyranosyl-2alpha,3beta, 19alpha-trihydroxyolean-12-en-28-oic acid, 28-O-beta-D-glucopyranoside by chemical and spectral data.

From the whole plant of Eclipta alba, a new triterpene saponin, named eclalbatin, together with alpha-amyrin, ursolic acid and oleanolic acid were isolated. The structure of eclalbatin has been established as 3-O-beta-D-glucopyranosyl-3-beta-hydroxy-olean-12-en-28-oic acid, 28-O-beta-D-arabinopyranoside (1) on the basis of chemical and spectral data.