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Using combined chromatographic methods, two new sesquiterpene glucosides, vulgarosides A (1) and B (2), and two known analogs ainsliaside E (3) and pumilaside A (4) were isolated from the aerial parts of Artemisia vulgaris. Their chemical structures were established by spectroscopic methods, including one and two-dimensional nuclear magnetic resonance (1 D and 2 D-NMR) spectroscopy and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). In addition, their cytotoxicity on five human cancer cell lines, including KB (epidermoid carcinoma), HepG2 (hepatocarcinoma), MCF7 (breast carcinoma), SK-Mel-2 (melanoma), and LNCaP (prostate cancer) was also evaluated by the SRB assay. However, none of the tested eudesmane sesquiterpene glycosides showed significant cytotoxicity (IC50>100 µM).

Three new glucosides, ziberthinosides A–C (1–3), and six known compounds, cleomiscosins A–D (4–7), sporogen AO-2 (8) and sapinofuranone A (9), were isolated from a methanol extract of Durio zibethinus fruit peels. Their chemical structures were elucidated by analyses of their 1 D/2D NMR and HR-ESI-MS data as well as by comparison with the literature values. The absolute configuration of sporogen AO-2 (8) was confirmed by ECD calculation. Of the isolates, compounds 8 and 9 were cytotoxic toward all MCF7, HepG2 and SK-LU-1 cell lines, with IC50 values ranging from 10.7 to 34.9 μM. Our results contribute to better understanding of the chemical constituents of the high valued durian fruit and their pharmacological effect, such as cytotoxicity.

Phytochemical investigation of a methanol extract of Panax pseudoginseng flower buds resulted in the isolation of 22 dammarane-type triterpenoid saponins, including three new compounds, pseudoginsenosides A-C (1-3), and 19 known analogs. Their chemical structures were identified by the comprehensive spectroscopic methods, including 1 D and 2 D NMR and mass spectra. In addition, their cytotoxic effects toward three human carcinoma cell lines, including liver (HepG2), breast (MCF7), and lung (A549) were also evaluated.

Two new phenolic glycosides, oroxylumosides A (1) and B (2), along with four known compounds darendoside A (3), leucosceptoside A (4), acteoside (5) and decaffeoylacteoside (6) were isolated from the stem bark of Oroxylum indicum. Their structures were elucidated by extensive analysis of the 1 D and 2 D NMR as well as HR-ESI-QTOF-MS. In addition, compounds 1 − 4 exhibited inhibitory effects on NO production in LPS-stimulated BV2 microglial cell line with IC50 values of 58.2 ± 2.9, 70.6 ± 3.5, 56.8 ± 2.8 and 61.1 ± 3.1 µM, respectively.

Using various chromatographic separations, three new acylated flavonoid glycosides, namely barringosides G–I (1–3), were isolated from the water-soluble extract of Barringtonia racemosa branches and leaves. The structure elucidation was performed by extensive analysis of the 1D and 2D NMR and HR-QTOF-MS data. Of the isolated compounds, barringoside I (3) showed moderate inhibitory effects on LPS-induced NO production in RAW264.7 cells with an IC50 of 52.48 ± 1.04 µM.

Phytochemical investigation of the branches and leaves of Alchornea annamica led to isolation of ten secondary metabolites, including two new megastigmane glucosides alnamicosides A (1) and B (2). The structure elucidation was confirmed by 1 D and 2 D NMR, ECD as well as HR-QTOF-MS experiments. The megastigmane derivatives 1 − 3 exhibited inhibitory effects on LPS-induced NO production in RAW264.7 cells with IC50 values of 78.72 ± 1.90, 77.40 ± 9.40 and 82.16 ± 4.56 µM, respectively. This is the first report on chemical constituents and biological activity of the plant A. annamica.

Chemical investigation of the marine-derived endophytic fungus Ascomycota sp. VK12 resulted in isolation and identification of a new compound, (3R)-(3′,5′-dihydroxyphenyl)butan-2-one (1) and five known ones: AGI-7 (2), sescandelin (3), sescandelin-B (4), 4-hydroxybenzaldehyde (5), and hydroxysydonic acid (6). The absolute configuration of 1 was determined by time-dependent density functional theory electronic circular dichroism, specific optical rotation, and NMR calculations. Compounds 1 and 2 showed cytotoxicity towards HepG2, MCF-7, and SK-Mel2 carcinoma cells, with IC50 values ranging from 48.6 to 96.5 µM. Compounds 1, 2, 4–6 displayed NO inhibitory effects in LPS-stimulated BV2 cells, with IC50 values in a range from 24.2 to 76.5 µM. Compound 2 further inhibited PGE2 overproduction, with an IC50 value of 25.3 µM. The inhibitory effects of 2 towards NO and PGE2 overproduction were found to have a close relationship with its suppression of iNOS and COX-2 protein expression, respectively.

In our search for anti-inflammatory constituents from Vietnamese plants, the methanolic extract of Helicteres viscida was found to exhibit inhibitory effect on LPS-induced NO production in RAW264.7 cells. Phytochemical investigation of this plant led to isolation of four sulphated flavones (1���4), including one new compound 5,3���,4���-trihydroxy-7-methoxy-8-O-sulphate flavone (1), and two pregnane-type steroids (5 and 6), including one new compound 7-epi-heligenin B (5). Their structures were elucidated by 1D and 2D NMR as well as HR-QTOF-MS experiments. Among isolated compounds, heligenin B (6) exhibited potent inhibitory effect on LPS-induced NO production in RAW264.7 cells with IC50 of 1.23 �� 0.05 ��M. The activity of 6 was comparable to that of the positive control cardamonin.

Using various chromatographic separations, three triterpene tetraglycosides (1–3), including one new compound, namely stichorrenoside E (1) along with thelenotoside B (2) and deacetyl thelenotoside B (3), were isolated from the MeOH extract of the Vietnamese sea cucumber Stichopus horrens. Their structures were confirmed by spectroscopic experiments, such as 1D and 2D NMR and HR-ESI-MS. Deacetylated thelenotoside B (3) is firstly isolated as a natural product. Among these compounds, thelenotoside B (2) showed strong cytotoxicities against five human cancer cell lines as HepG2, KB, LNCaP, MCF7 and SK-Mel2 with the IC50 values from 0.95 ± 0.08 to 1.90 ± 0.13 μM, whereas stichorrenoside E (1) and deacetyl thelenotoside B (3) exhibited significant activities with the IC50 values from 6.87 ± 0.25 to 11.62 ± 1.05 μM.

Two new guaiane sesquiterpene lactones, vulgarolides A and B (1 and 2), were isolated from Artemisia vulgaris aerial parts using various chromatographic separations. The structure elucidation was performed by combination of spectroscopic experiments including 1D and 2D NMR, HR ESI MS, and CD. Their in vitro cytotoxic activities against five human cancer cell lines were also evaluated using SRB method.

Using combined chromatographic separations, two new steroid glycosides namely pentacerosides A (1) and B (2), and four known compounds were isolated from the methanol extract of the starfish Pentaceraster gracilis. Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, ROESY, and FT-ICR-MS) and by comparing obtained results to the literature values. Among the isolated compounds, only maculatoside (5) showed significant cytotoxic effect against Hep-G2 (IC50 = 16.75 ± 0.69 μM) and SK-Mel2 (IC50 = 19.44 ± 1.45 μM) cell lines and moderate effect on KB (IC50 = 36.53 ± 0.78 μM), LNCaP (IC50 = 39.75 ± 3.34 μM), and MCF7 (IC50 = 47.34 ± 7.01 μM) cell lines.

Six iridoid derivatives (1–6), including two new compounds myrmecodoides A and B (1 and 2), were isolated from the ant-plant Myrmecodia tuberosa. Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, NOESY and HR-ESI-MS) and by comparison with the literature values. Among isolates, 3 and 4 exhibit weak antibacterial effect against Staphylococcus aureus subsp. aureus with MIC value of 100.0 μg/mL.