Bithiophene and coumestan derivatives from Eclipta prostrata (L.) L. and their hepatoprotective activity.

One new bithiophene derivative, 5-(but-3-en-1-yn-1-yl)-5'-(methoxymethyl)-2,2'-bithiophene (1), along with twelve known compounds, senecioester (2), tiglinsaureester (3), 5-acetoxymethyl-2'-(but-3-en-1-yn-1-yl)-2,5'-bithiophene (4), 5-(4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (5), 5-hydroxymethyl-(2,5':2',5'')-terthienyl tiglate (6), 5-hydroxymethyl-(2,5':2',5'')-terthienyl agelate (7), 5- hydroxymethyl-2,5':2',5''-terthiophene dimethylacrylate (8), 5-methoxymethyl-2,2':5',2''-terthiophene (9), α-terthiophene (10), 1,3,8,9-tetrahydroxycoumestan 3-sulfate (11), demethylwedelolactone (12), and wedelolactone (13) were isolated from the methanol extract of aerial parts of Eclipta prostrata (L.) L. All isolated compounds were evaluated for the protective ability on the HepG2 cells. At the concentration of 100 µM, compounds 11-13 showed the highest hepatoprotective effects, with HepG2 cell viability ranging from 38.68% to 48.54%. Bithiophenes showed higher hepatoprotective cell viability than terthiophenes.

Symplosaponins A-D: New acylated oleanane-type triterpene saponins from Symplocos cochinchinensis and their hepatoprotective effect.

Four new acylated oleanane-type triterpene saponins, symplosaponins A-D (1-4) were successfully isolated from the leaves of Symplocos cochinchinensis (Lour.) S. Moore, alongside with five known compounds (5-9), 2-methoxy-4-prop-1-enylphenyl-1-O-ß-D-apiofuranosyl-(1 â†’ 6)-ß-D-glucopyranoside (5), and 1-[O-ß-d-xylopyranosyl-(1 â†’ 6)-O-ß-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6), 6-O-p-coumaroylsucrose (7), arillatose B (8), and (-)-secoisolariciresinol-O-ß-D-glucopyranoside (9). The structures of these compounds were elucidated through spectroscopic methods, comparison with existing data, and chemical methods. Furthermore, all compounds were assessed for their impact on hepatocellular viability using the Resazurin reduction assay. These investigations aimed to explore the potential hepatoprotective properties of isolated compounds. As a result, 1-[O-ß-d-xylopyranosyl-(1 â†’ 6)-O-ß-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6) and (-)-secoisolariciresinol-O-ß-D-glucopyranoside (9) demonstrated statistically significant hepatoprotective activity in a concentration-dependent manner.

A Pair of Undescribed Alkaloid Enantiomers from Marine Sponge-Derived Fungus Hamigera avellanea and Their Antimicrobial and Cytotoxic Activities.

From marine sponge-associated fungus Hamigera avellanea, thirteen secondary metabolites including a pair of undescribed alkaloid enantiomers (+)-hamiavemin A (4S) (+)-1 and (-)-hamiavemin A (4R) (-)-1. Compound 1 was enantiomers resolved by the Chiralpak AS-3 column, using a hexane/isopropanol mobile phase. Their structures were determined based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. The absolute configuration of (+)-1 and (-)-1 were assigned tentatively by ECD calculations. Among the isolates, compound 6 showed strongest antibacterial activity against Enterococcus faecalis, Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella enterica, and Candida albicans with the MIC values of 2, 2, 16, 32, 64, and 16 µg/mL, respectively, which were stronger than that of the positive control compound, kanamycin (MIC values ranging from 4 to 128 µg/mL). In addition, compounds 1, 2, and 9 showed moderate cytotoxic activity against three cancer cell lines, HepG2, A549, and MCF-7 with the IC50 values ranging from 55.35±1.70 to 83.02±2.85 µg/mL.

Discovery of Four New Compounds from Macropanax membranifolius and Their Cytotoxic Activity.

A phytochemical investigation of the methanolic extract of the Macropanax membranifolius C.B. Shang leaves led to the isolation of three new flavans, (2R,3R)-4'-O-methylcatechin 5-O-ß-D-glucopyranoside (1), (2S,3S)-4'-O-methylcatechin 5-O-ß-D-glucopyranoside (2), (2S,3R)-4'-O-methylcatechin 5-O-ß-D-glucopyranoside (3), one new triterpene glycoside 3-O-ß-D-xylopyranosyl-(1→6)-[ß-D-xylopyranosyl-(1→2)]-ß-D-glucopyranosyl-oleanolic acid 28-O-ß-D-glucopyranoside (4), together with nine known compounds (5-13). Their chemical structures were elucidated based on HR-ESI-MS, NMR spectroscopic data. The absolute configurations of compounds 1-3 were established by electronic circular dichroism (ECD) spectra. At concentration of 20 µM, compounds 1-13 showed the percentages of dead cell in the range of 2.14 % to 33.61 % against KB, HepG2, HL60, P388, HT29, and MCF7 cancerous cell lines by SRB assay.

Three new chromanes and one new flavone C-glycoside from Mallotus apelta.

Three new chromanes, malloapeltas J-L (1-3), and one new flavone C-glycoside, malloflavoside (4), together with four known compounds, apigenin 6-C-ß-D-xylopyranosyl-8-C-α-L-arabinopyranoside (5), apigenin 6-C-ß-D-glucopyranosyl-8-C-α-L-arabinopyranoside (6), apigenin 7-O-ß-D-apiofuranosyl-(1→2)-ß-D-glucopyranoside (7), and acantrifoside E (8) were isolated from the methanol extract of the leaves of Mallotus apelta. Their chemical structures were determined using spectroscopic methods, including 1D, 2D NMR, and HR-ESI-MS methods. All the isolated compounds were evaluated their cytotoxic activity against human prostate cancer (PC-3) and human breast cancer (MCF-7) cells, but none of them showed cytotoxicities on both human cancer cell lines.

Furostane Saponins from the Seeds of Allium ramosum and Their Lipid Accumulation Inhibitory Activity.

Three new furostane saponins, ramofurosides A-C (1-3), and two known saponins, fistulosaponin B (4) and (25R)-26-O-ß-D-glucopyranosyl-1ß,3ß,26-trihydroxyfurosta-5,20(22)-diene-1-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (5) were isolated from the methanol extract of Allium ramosum seeds. Their structures were identified based on spectroscopic evidence and comparison with those reported in the literature. All compounds were evaluated for reduction of lipid accumulation in HepG2 cell lines. As a result, compounds 1 and 3 showed a significant reduction in total lipid content by 27.93±3.05 and 27.54±1.68 %, respectively, at a concentration of 100 µM.

Sulfated Naphthopyrones and Anthraquinones from the Vietnamese Crinoid Comanthus delicata.

Three new sulfated naphthopyrone derivatives namely delicapyrons F-H (1-3) and two new sulfated anthraquinone derivatives namely delicaquinons A (4) and B (5), together with 6-methoxycomaparvin-5-methylether-8-O-sodium sulfate (6), 6-methoxycomaparvin-8-O-sodium sulfate (7), comaparvin-8-O-sodium sulfate (8), and 3-propyl-1,6,8-trihydroxy-9,10-anthraquinone-6-O-sodium sulfate (9) were isolated from the Vietnamese crinoid Comanthus delicata. Their chemical structures were elucidated by extensive analysis of the one dimensional (1D) and 2D-NMR, high resolution electrospray ionization quadrupole time-of-flight (HR-ESI-QTOF) mass spectra as well as calculation of optical rotation. In addition, significant cytotoxicity was observed for 6 against LNCaP (prostate cancer) cell line with IC50 value of 20.29 ± 2.43 µM, whereas moderate or weak cytotoxic effects were observed for 1-3 and 5-8 on SK-Mel-2 (melanoma) cell line and 7 and 8 against LNCaP cell line, with IC50 values ranging from 49.96 ± 1.74 to 76.92 ± 5.85 µM.

One new phenylpropanoid glycoside from Myxopyrum smilacifolium with α-glucosidase inhibitory activity.

One new phenylpropanoid glycoside, myxosmoside I (1) and six known compounds, arenarioside (2), verbacoside (3), 3-formylindole (4), 5-hydroxymethyl furfural (5), D-manitol (6), and glycerol monooleate (7) were isolated from the roots of Myxopyrum smilacifolium (Wall.) Blume. Their chemical structures were determined by 1D-, 2D-NMR, and mass spectra, chemical methods, and compared with those reported in the literature. All compounds were evaluated for α-glucosidase inhibitory effect. Among them, phenylpropanoid glycosides 1-3 significantly inhibited α-glucosidase activity with IC50 values of 30.0 ± 0.9, 66.6 ± 2.3, and 36.9 ± 2.0 µM, respectively.

Cembranoids from the Vietnamese soft coral Sarcophyton ehrenbergi.

Using various chromatographic separations, two new cembranoids, ehrenbergols F and G (1 and 2), along with three known analogs ehrenbergol D (3), (+)-isosarcophine (4) and sinulariol Z2 (5) were isolated from the soft coral Sarcophyton ehrenbergi. The structural elucidation was done by extensive analysis of the 1 D and 2 D NMR, HR-ESI-QTOF-MS as well as CD experiments. In addition, compounds 1 (IC50 of 38.38 ± 2.89 µM), 3 (IC50 of 37.14 ± 3.22 µM) and 4 (IC50 of 45.01 ± 2.49 µM) revealed moderate inhibitory activity on LPS-induced NO production in RAW264.7 cells, whereas 2 (IC50 of 73.32 ± 1.95 µM) and 5 (IC50 of 64.48 ± 4.93 µM) exhibited weak effect.

Dihydrostilbene glycosides from Camellia sinensis var. assamica and their cytotoxic activity.

Three undescribed dihydrostilbene glycosides, 3,5-dihydroxyldihydrostilbene 4'-O-[6''-O-(4'''-hydroxylbenzoyl)]-ß-D-glucopyranoside (1), 3,5-dihydroxyldihydrostilbene 4'-O-(6''-O-galloyl)-ß-D-glucopyranoside (2), and 3,5-dihydroxyldihydrostilbene 4'-O-[6''-O-(3''',4'''-dimethoxyl)galloyl]-ß-D-glucopyranoside (3), and seven known compounds, kaempferol 3-O-ß-D-glucopyranoside (4), isoquercitrin (5), kaempferol 3-O-α-L-rhamnoside (6), quercitrin (7), (6S,9R)-roseoside (8), (-)-epicatechin 3-O-gallate (9), and (-)-epigallocatechin 3-O-gallate (10) have been isolated from the methanol extract of the leaves of Camellia sinensis var. assamica (J.W.Mast.) Kitam. (synnonym of Camellia assamica (Mast.) H.T.Chang) (Theaceae). Their structures were elucidated by spectroscopic methods (1 D-, 2 D-NMR) and mass spectra. All compounds were evaluated for cytotoxic activity against human oral cancer (CAL27) and human breast cancer (MDAMB231) cell lines. Compound 10 showed significant cytotoxic activity against CAL27 and MDAMB231 cell lines with IC50 values of 9.78 ± 0.25 and 3.27 ± 0.18 µM, respectively, compared to those of positive control, capecitabine (IC50 values of 8.20 ± 0.75 and 5.20 ± 0.89 µM).

A new cytotoxic compound from the leaves of Styrax annamensis Guillaumin.

New propene derivative 1-(3',4'-methylenedioxyphenyl)-2-(2''-hydroxy-5-(3'''-hydroxypropyl)-3''-methoxyphenyl)prop-2-en-1-one (1), along with three known triterpenoids ursolic acid (2), pomolic acid (3), and maslinic acid (4) were isolated from the leaves of Styrax annamensis species. All structures were assigned by spectroscopic analysis. Compound 1 showed potent cytotoxicity against four cancer cell lines (KB, HepG2, Lu, and MCF7) with the IC50 values of 3.19, 2.87, 2.33, and 2.44 µM, respectively.

Six new iridoid glucosides from Myxopyrum smilacifolium (Wall.) Blume.

Six new iridoid glycosides, myxosmosides A-F (1-6) were isolated from the roots of Myxopyrum smilacifolium (Wall.) Blume. Their chemical structures were determined using, 1D-, 2D-NMR, and mass spectra and chemical methods.

The in vitro and in vivo anti-inflammatory activities of alphitonin-4-O-ß-D-glucopyranoside.

The anti-inflammatory compound, alphitonin-4-O-ß-D-glucopyranoside (1), has previously been isolated in the leaves of Artokapus tonkinensis and synthesised from taxifolin. This study aimed to investigate the inhibitory effect of this compound on inflammatory cytokines, including tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1, IL-6 and IL-10, in RAW264.7 macrophages and in an arthritis animal model. Compound 1 dose-dependently decreased the production of TNF-α, IL-1 and IL-6 in lipopolysaccharide-stimulated RAW264.7 cells. In contrast, the level of anti-inflammatory IL-10 increased. In a collagen antibody-induced arthritis BALB/c mouse model, compound 1 at a dose of 125 and 250 mg/kg body weight significantly decreased arthritis incidence in comparison with dexamethasone.

Sesquiterpene derivatives from marine sponge Smenospongia cerebriformis and their anti-inflammatory activity.

Using various chromatographic methods, five new sesquiterpene derivatives named smenohaimiens A-E (1-5) and five known, 19-hydroxy-polyfibrospongol B (6), ilimaquinone (7), dictyoceratin C (8), polyfibrospongol A (9), and polyfibrospongol B (10) were isolated from the marine sponge Smenospongia cerebriformis Duchassaing & Michelotti, 1864. Their structures were assigned by 1D, 2D NMR spectroscopic analysis, HR ESI MS, and calculations of the electron circular dichroism spectra. All compounds were evaluated for the inhibitory activity against NO production in lipopolysaccharide-stimulated in BV2 microglia cells. As the results, compound 7 significantly inhibited NO production with the IC50 value of 10.40±1.28µM. The remaining compounds showed moderate inhibitory NO production activities with IC50 values ranging from 24.37 to 30.43µM.

Steroidal constituents from the starfish Astropecten polyacanthus and their anticancer effects.

Using various chromatographic methods, four new steroids, astropectenols A-D (1-4), along with three known compounds (5-7) were isolated from a methanol extract of the starfish Astropecten polyacanthus. The structure elucidation was confirmed by spectroscopic methods, including one dimensional (1D)-, 2D-NMR and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The CH2Cl2 fraction and compound 7 exhibit potent cytotoxic effects against HL-60 human leukemia cells with the IC50 of 8.29 µg/mL and 2.70 µM, respectively, comparing to the positive control, mitoxantrone (IC50=6.80 µM). When HL-60 cells were treated with the CH2Cl2 fraction or compound 7, several apoptosis events like chromatin condensation and the increase of the population of sub-G1 hypodiploid cells were observed. Investigations for the possible mechanism underlying the induction of apoptosis showed that CH2Cl2 fraction or compound 7 induced apoptosis through down-regulation of Bcl-2, up-regulation of Bax, cleavage of caspase-9, cleavage of caspase-3 and cleavage of poly(ADP-ribose) polymerase (PARP) in HL-60 cells. Furthermore, the apoptosis induction of HL-60 cell by CH2Cl2 fraction or compound 7 was attended by the decreasing of phospho-extracellular signal-regulated kinase (ERK) 1/2 and C-myc. These results indicated that the CH2Cl2 fraction and compound 7 could induce the apoptosis of HL-60 cells via the inactivation of ERK 1/2 and the decrease of C-myc. Our finding suggested the potential using of the CH2Cl2 fraction and compound 7 for leukemia treatment.

Pyrrole and furan oligoglycosides from the starfish Asterina batheri and their inhibitory effect on the production of pro-inflammatory cytokines in lipopolysaccharide-stimulated bone marrow-derived dendritic cells.

Three new pyrrole oligoglycosides, astebatheriosides A-C (1-3), and a new furan oligoglycoside, astebatherioside D (4), were isolated from the starfish Asterina batheri by various chromatographic methods. Their structures were elucidated by spectroscopic and chemical methods. Compounds 2, 3, and 4 moderately inhibited IL-12 p40 production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) with IC50 values of 36.4, 31.6, and 22.8µM, respectively.