Three New Spirostan Glycosides from Dracaena cochinchinensis with NO Production Inhibitory and Antimicrobial Activity.

Three new spirostan glycosides, dracochinosides A-C (1-3), and four known steroidal glycosides (4-7) were isolated from the aerial parts of Dracaena cochinchinensis (Lour.) S.C.Chen. Their chemical structures were determined by the IR, HR-ESI-MS, 1D-, and 2D-NMR spectra. Compounds 1-3, 6 and 7 inhibited nitric oxide production in LPS activated RAW 264.7 cells with IC50 values ranging from 57.5 to 92.8 µM. In addition, all the isolated compounds exhibited at least one of seven tested microbial strains with the MIC values ranging from 0.016 to 0.128 mg/mL. This is the first report of compounds 5-7 from the genus Dracaena.

Phyllanretiosides A and B: Two Undescribed Compounds from Phyllanthus reticulatus with Nitric Oxide Production Inhibition and Antimicrobial Activity.

Phytochemical study on the methanol extract of the leaves of Phyllanthus reticulatus led to the isolation of two new compounds, phyllanreticosides A (1) and B (2) together with ten known ones (3-12). Their chemical structures were determined by HR-ESI-MS, NMR, and ECD spectra in comparison with the literature. Three ellagitannins, phyllanreticoside A (1), corilagin (3), and phyllanthusiin C (4) inhibited lipopolysaccharide(LPS)-induced nitric oxide production in RAW 264.7 cells with IC50 values of 63.2, 83.2, and 5.6 µM, respectively. In addition, compounds 1, 3, and 4 exhibited significantly antimicrobial activity (MICs: 16-128 µg/mL) towards some of seven microbial strains, including Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, and Candida albicans.

Cytotoxic Effects of Oleanane-type Saponins from Lysimachia laxa.

Phytochemical investigation of the methanol extract of the aerial parts of Lysimachia laxa led to the isolation of four new oleanane-type saponins, lysimosides A-D (1-4) and one known compound, lysimachigenoside B (5). Their structures were elucidated using a combination of HR-ESI-MS, 1D and 2D-NMR spectral data, chemical methods, and comparison with previous literature. The cytotoxic activity of these compounds was evaluated against human lung cancer (A-549) and human breast cancer (MCF-7) cell lines. All compounds exhibited cytotoxic activity against A-549 and MCF-7 cell lines with IC50 values ranging from 6.1 to 16.0 µM, comparable to the positive control, mitoxantrone. Interestingly, oleanane-type saponins with an acetyl group (2-4) exhibited increased cytotoxic activities compared to those without an acetyl group (1).

Five New Furostanol Glycosides from the Fruits of Tribulus terrestris with NO Production Inhibitory Activity.

Eight furostanol glycosides including five undescribed compounds, named tribufurostanosides A-E (1-5), and three known ones (6-8) were isolated from the fruits of Tribulus terrestris L. Their chemical structures were determined by the IR, HR-ESI-MS, 1D-, and 2D-NMR spectra. Furostanols 1-8 significantly inhibited nitric oxide production in LPS activated RAW 264.7 cells with IC50 values ranging from 14.2 to 64.7 µM, compared to that of the positive control compound, dexamethazone (IC50 13.6 µM).

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.

Hericium VN, an undescribed compound isolated from Hericium erinaceus and its cytotoxic activity on human brain astrocytoma.

Hericium erinaceus is a species of mushroom with high nutritional value that is used mainly as food in tropical countries. Phytochemical study of H. erinaceus led to the isolation of an undescribed compound, named as hericium VN (1), together with nine known compounds, 1-(2-formyl-1-pyrrolyl)butanoic acid (2), herierin III (3), 5'-(methylthio)adenosine (4), adenosine (5), nicotinic acid (6), (22E,24R)-5α,8α-epidioxyergosta-6,9(11),22-trien-3ß-ol (7), 5α,8α-peroxycerevisterol (8), (22E,24R)-5α,8α-epidioxy-egosta-6,22-diene 3-O-ß-D-glucopyranoside (9), and cerevisterol (10) based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. The absolute configuration of compound 1 was determined by experimental combined with calculated electronic circular dichroism spectra. Compound 7 exhibited cytotoxic effects against brain tumor cell line CCF-STTG1 with the IC50 value of 15.50 µM, compared to that of the positive control compound, doxorubicin, which showed IC50 value of 15.84 µM.

Undescribed Lignanamide and Flavone C-Glucoside Isolated from the Aerial Parts of Piper Samentosum with NO Production Inhibitory Activity in LPS Activated RAW 264.7†Cells.

In this study, two undescribed compounds (1 and 2), together with eight known compounds (3-10) were isolated from the aerial parts of Piper samentosum by various chromatography methods. Their chemical structures were determined to be 7'''-oxolyciumamide N (1), vitexin 2''-O-ß-D-(6'''-feruloyl)-glucopyranoside (2), 1,2-dihydro-6,8-dimethoxy-7-hydroxy-1-(3,4-dihydroxyphenyl)-N1,N2-bis-[2-(-hydroxyphenyl)ethyl]-2,3-napthalene dicarboamide (3), vitexin 6''-O-ß-D-glucopyranoside (4), vitexin 2''-O-α-L-rhamnopyranoside (5), methyl 2-hydroxybenzoate-2-O-ß-D-apiofuranosyl-(1→2)-O-ß-D-glucopyranoside (6), ficuside G (7), methyl 2-O-ß-D-glucopyranosylbenzoate (8), methyl 2,5-dihydroxybenzoate-5-O-ß-D-glucopyranoside (9), and 3,7-dimethyloct-1-ene-3,6,7-triol 6-O-ß-D-glucopyranoside (10) by spectroscopic data analysis including HR-ESI-MS, 1D-, and 2D-NMR spectra. Compounds 1-5 inhibited nitric oxide production in LPS-stimulated RAW264.7 macrophages with the IC50 values of 27.62, 74.03, 38.54, 70.39, and 44.95 µM, respectively. The NMR data of 9 were firstly reported herein.

Undescribed sesquiterpene-diterpene heterodimers from the fruits of Aphanamixis polystachya selectively modulate inflammatory markers in RAW 264.7 cells.

Aphanapolystachones A-C (1-3), three undescribed sesquiterpene-diterpene heterodimers, were obtained from the fruits of Aphanamixis polystachya. Their structures and absolute configurations were identified by extensive analysis of HR-ESI-MS, NMR, experimental and TD-DFT calculated ECD spectra. The biosynthetic pathway of them was also proposed, which is produced by key intermolecular Diels-Alder [4 + 2]-cycloaddition reaction between a guaiane sesquiterpene and an acyclic diterpene. Compounds 1-3 inhibited NO production in LPS activated RAW 264.7 cells with the IC50 values of 1.7 ± 0.2, 3.0 ± 0.3, 5.3 ± 0.3 µM, respectively, lower than that of the positive control L-NMMA (31.5 ± 2.6 µM). In addition, compounds 1-3 significantly reduced IL-6 secretion at diluted concentration of 0.4 µM.

Alkaloids and Lignans from the Aerial Parts of Rauvolfia tetraphylla Inhibit NO Production in LPS-activated RAW 264.7 Cells.

Three previously undescribed compounds named rauvolphyllas A-C (1-3), along with thirteen known compounds, 18ß-hydroxy-3-epi-α-yohimbine (4), yohimbine (5), α-yohimbine (6), 17-epi-α-yohimbine (7), (E)-vallesiachotamine (8), (Z)-vallesiachotamine (9), 16S-E-isositsirikine (10), Nb -methylisoajimaline (11), Nb -methylajimaline (12), ajimaline (13), (+)-lyoniresinol 3α-O-ß-D-glucopyranoside (14), (+)-isolarisiresinol 3α-O-ß-D-glucopyranoside (15), and (-)-lyoniresinol 3α-O-ß-D-glucopyranoside (16) were isolated from the aerial parts of Rauvolfia tetraphylla L. Their chemical structures were elucidated based on the extensive spectroscopic interpretation of HR-ESI-MS, 1D and 2D NMR spectra. The absolute configurations of 2 and 3 were determined by experimental ECD spectra. Compounds 5, 6, 7, and 11-13 exhibited nitric oxide production inhibition activity in LPS-activated RAW 264.7 cells with the IC50 values of 79.10, 44.34, 51.28, 33.54, 37.67, and 28.56 µM, respectively, compared to that of the positive control, dexamethasone, which showed IC50 value of 13.66 µM. The other isolates were inactive with IC50 values over 100 µM.

Four Undescribed compounds Isolated from the Aerial Parts of Phyllanthus cochinchinensis with Antimicrobial Activity and NO Production Inhibitory Activity in LPS Activated RAW 264.7 Cells.

Four previously undescribed compounds named phyllancosides A and B (1 and 2), and phyllancochines A and B (3 and 4) together with ten known compounds (5-14) were isolated from the aerial parts of Phyllanthus cochinchinensis Spreng. Their chemical structures were elucidated on the basis of comprehensive analysis of IR, HR-ESI-MS, 1D and 2D NMR spectra. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) spectra. Compounds 3, 4, and 10 showed antimicrobial activity against E. faecalis, S. aureus, and B. cereus with the MIC values in range of 32-256 µg/mL. Compound 11 inhibited E. faecalis and B. cereus, and 7 inhibited S. aureus with the MIC values in range of 64-128 µg/mL. In addition, compounds 1, 3, 4, 8, and 9 showed significantly NO production inhibitory activity in LPS activated RAW 264.7 cells with IC50 values ranging from 36.57 to 56.34 µM.

Undescribed Triterpenes from the Leaves of Syzygium myrsinifolium with Their α-Glucosidase and α-Amylase Inhibition Activity.

Two undescribed triterpenes, syzyfolium A (1) and syzyfolium B (2), together with twelve known compounds, terminolic acid (3), actinidic acid (4), piscidinol A (5), threo-dihydroxydehydrodiconiferyl alcohol (6), lariciresinol-4-O-ß-D-glucoside (7), icariol A2 (8), 14ß,15ß-dihydroxyklaineanone (9), garcimangosone D (10), (+)-catechin (11), myricetin-3-O-α-L-rhamnopyranoside (12), quercitrin (13), and 3, 4, 5-trimethoxyphenyl-(6'-O-galloyl)-O-ß-D-glucopyranoside (14) were isolated from the leaves of Syzygium myrsinifolium. Their chemical structures were determined by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 3 and 4 inhibited significantly α-glucosidase with IC50 values of 23.99 and 36.84, respectively, and compounds 1 and 2 inhibited significantly α-amylase with IC50 values of 35.48 and 43.65 µM, respectively.

Four Steroidal Saponins from the Trunks of Dracaena cambodiana with Inhibition of NO Production in LPS Activated RAW264.7 Cells.

Dracaena cambodiana Pierre ex Gagnep. is well known as a medicinal plant and widely distributed in Vietnam. Phytochemical investigation on the trunks of D. cambodiana lead to the isolation of four undescribed compounds (1-4) together with seven known ones (5-11). Their structures were determined to be pennogenin-24-yl-O-ß-D-glucopyranoside (1), 17α-hydroxycambodianoside C (2), (25R)-27-hydroxypenogenin 3-O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (3), (3ß,25R)-17α,22α-dihydroxy-furost-5-en-3-yl-O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (4), dracagenin A (5), 1-O-ß-D-glucopyranosyl-2-hydroxy-4-allylbenzene (6), 1-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranosyl-2-hydroxy-allylbenzene (7), 2-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranosyl-1-hydroxy-allylbenzene (8), cinnamrutinoside A (9), icariside D1 (10), and seco-isolariciresinol 9-O-ß-glucopyranoside (11) by extensive spectroscopic investigation, HR-ESI-MS, 1D and 2D NMR spectra. The anti-inflammatory activity of the isolated compounds was evaluated on macrophages. Compounds 1-6 significantly inhibited nitric oxide production in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Among them, compound 1 showed the best inhibitory activity with an IC50 value of 8.90±0.56 µM.

Phytochemical constituents from the rhizomes of Kaempferia parviflora Wall. ex Baker and their acetylcholinesterase inhibitory activity.

Phytochemical study on the rhizomes of Kaempferia parviflora led to the isolation of twenty-three compounds including six phenolic glycosides (1-6), thirteen flavones (7-19), and five phenolic compounds (20-23). Of these, the new compounds were determined to be 2,4-dihydroxy-6-methoxyacetophenone-2-ß-D-apiofuranosyl-(1→6)-ß-D-glucopyranoside (1), 2-hydroxy-4-propionyl-phenyl O-ß-D-glucopyranoside (2), and 4-hydroxy-3,5-dimethoxyacetophenone 8-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranoside (3) and named as kaempanosides A-C, respectively. Their chemical structures were established based on HR-ESI-MS, 1D and 2D NMR spectra. All compounds 1-23 exhibited acetylcholinesterase inhibitory activity with IC50 values ranging from 57.76 to 253.31 µM.

Chryroxosides A-E: five new triterpene saponins from the leaves of Chrysophyllum roxburghii G.Don. and their cytotoxic activity.

Five undescribed oleanane triterpene glycosides named chryroxosides A-D (1-5), together with five known compounds (6-10) were isolated from the leaves of Chrysophyllum roxburghii G.Don. Their chemical structures were elucidated by extensive spectroscopic data analyses including IR, HR-ESI-MS, 1D and 2D NMR). Compounds 1, 3, and 5 showed cytotoxic effects against KB, HepG2, HL60, P388, HT29, and MCF7 cell lines with the IC50 values ranging from 14.40 to 52.63 µM compared to the positive control compound (ellipticine) with the IC50 values ranging from 1.34 to 1.99 µM.

Glycoside constituents of Camellia amplexicaulis and their α-glucosidase inhibitory activity.

Four new glycosides, named amplexicosides A-D (1-4), and five known compounds: benzyl 2-[ß-D-glucopyranosyl-(1→6)-ß-D-glucopyranosyloxy]-benzoate (5), benzyl 2-neohesperidosyloxy-6-hydroxybenzoate (6), chrysandroside A (7), chrysandroside B (8) and camelliquercetiside C (9) were isolated from the branches and leaves of Camellia amplexicaulis (Pit.) Cohen-Stuart. Their structures were elucidated using HR-ESI-MS and 1D- and 2D-NMR spectra and compared to reported NMR data. All of the isolated compounds were screened in an α-glucosidase assay. Compounds 4, 8, and 9 significantly inhibited α-glucosidase with respective IC50 values of 254.9 ± 4.2, 304.8 ± 11.9 and 228.1 ± 16.4 µM.

Chemical constituents from the heterotrophic marine microalgae Aurantiochytrium sp. SC145 and their antimicrobial activities.

One new indol, N-methoxymethyltryptophol (1), one new phenolic, (2 R)-2-(4-hydroxyphenyl)ethyl 2-hydroxy-3-phenylpropanoate (2) and fifteen known compounds (3-17) were isolated from the methanol extract of the fermentation of marine microalgae Aurantiochytrium sp. SC145. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis, HR-ESI-MS, quantum chemical calculation methods and by comparing their NMR data with those reported in the literature. All compounds were evaluated for their antimicrobial activities against microorganisms. Compounds 2, 3 and 11 significantly exhibited antimicrobial activities on all tested Gram-(+), Gram-(-) bacteria and the yeast C. albicans with MIC values ranging from 32 to 256 µg/mL.

Four New Steroidal Saponins from the Roots of Dracaena cambodiana with NO Production Inhibition Activity in LPS Activated RAW 264.7 Cells.

Seven steroidal saponins including three new 16,23-cyclocholestanes (1-3) and one new pregane (4) were isolated from the roots of Dracaena cambodiana Pierre ex Gagnep. Their chemical structures were elucidated to be (23R,25R)-26-O-ß-D-glucopyranosyl-16,23-cyclocholesta-5,17(20)-dien-22-one-3ß,16α,26-triol-3-O-α-L-rhamnopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→3)]-ß-D-glucopyranoside (1), (23R,25R)-26-O-ß-D-glucopyranosyl-16,23-cyclocholesta-5,17,20(22)-trien-3ß,22,26-triol-3-O-α-L-rhamnopyranosyl-(1→3)-ß-D-glucopyranoside (2), (23R,25R)-16,23-cyclocholesta-5,16,20(22)-trien-3ß,22,26-triol-3-O-α-L-rhamnopyranosyl-(1→3)-ß-D-glucopyranoside (3), 3ß-[(O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-gluco-pyranosyl)oxy]-pregna-5,17(20)-diene-16-one-20-carboxylic acid 4''''-O-ß-D-glucopyranosylisopentyl ester (4), cambodianoside A (5), diosbulbiside C (6), and diosbulbiside D (7), by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1 and 4-7 inhibited nitric oxide (NO) production in lipopolysaccharide activated RAW 264.7 cells with IC50 values ranging from 19.03±1.84 to 67.92±3.81 µM, whereas compounds 2 and 3 were inactive with IC50 values over 100 µM.

Three Undescribed Iridoid Derivatives Isolated from the Fruits of Vitex trifolia with Their Cytotoxic and Antimicrobial Activities.

Vitex trifolia L. is a medicinal plant and widely distributed in the northern mountainous areas of Vietnam. Phytochemical study on the fruits of this plant led to the isolation of nine iridoid derivatives (1-9) including three undescribed compounds (1-3). Their structures were elucidated to be 3''-hydroxyscrophuloside A1 (1), 3''-hydroxycallicoside D (2), 2'-p-hydroxybenzoylaucubin (3), 6'-p-hydroxybenzoylmussaenosidic acid (4), nishindaside (5), agnuside (6), 10-O-vanilloylaucubin (7), 6'-O-p-hydroxybenzoyl-gardoside (8), and buddlejoside B (9) based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1, 2, 4, and 8 significantly posessed anti-barterial activity against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa strains with MIC values in range of 16-64 µg/mL. At concentration of 20 µM, compounds 1-9 did not show cytotoxic effects against human lung cancer cells (PC9).

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.

Four New Stilbene Derivatives Isolated from Gnetum latifolium var. funiculare Markgr. and Their Inhibition of NO Production in LPS-activated RAW264.7 Cells.

Gnetum latifolium var. funiculare Markgr. is a medicinal plant and widely distributed in mountainous areas of Vietnam. Phytochemical investigation on the trunks of this plant afforded eight stilbene derivatives (1-8) including for new compounds (1-4). Their structures were determined based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. Among the isolates, compounds 1-3 showed moderate NO production inhibition in LPS-activated RAW264.7 cells with the IC50 values ranging from 46.81 to 68.10 µM, compounds 4 and 6 showed weak effects with the IC50 values of 96.57 and 79.46 µM, respectively, compared to that of the positive control compound, dexamethasone (IC50 14.20 µM).