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Analysis of an antimicrobial extract prepared from culture broth of the marine-derived actinomycete Nocardiopsis sp. (strain G057) led to the isolation of twelve compounds, 1–12. Compound 1 (2-[(2 R-hydroxypropanoyl)amino]benzamide) was found to be a new enantiomeric isomer while compounds 2 (3-acetyl-4-hydroxycinnoline) and 3 (3,3′-bis-indole) were isolated from a natural source for the first time. The structures of 1 – 12 were determined by analyses of MS and 2D NMR data. All compounds were evaluated for their antimicrobial activity against a panel of clinically significant microorganisms. Compound 1 selectively inhibited Escherichia coli (MIC: 16 μg/mL). Compounds 2 and 3 exhibited antimicrobial activity against several strains of both Gram-positive and Gram-negative bacteria, and the yeast Candida albicans. Cytotoxic evaluation of compounds 1 – 3 against four cancer cell lines (KB, LU-1, HepG-2 and MCF-7) indicated that compound 3 produced a weak inhibition against KB and LU cell lines. Two remaining compounds, 1 and 2 were not cytotoxic, even at the concentration of 128 μg/mL.

Seventeen bacterial strains were isolated from 9 marine mud samples from the inshore environments of the East Sea. Four bacterial strains showed an inhibition against all tested microorganisms Staphylococcus aureus ATCC10832, Escherichia coli JM109, and Fusarium oxysporum. 16S rRNA sequences of four bacterial strains were obtained by PCR using specific primers. PCR products were cloned into E. coli DH5a using pJET1.2 blunt vector. The recombinant plasmids were sequenced and the lengths of these 16S rRNA sequences were ~930bp. The 16S rRNA sequence from the four bacterial DB1.2, DB1.2.3, DB4.2 and DB5.2 strain showed a high identity of 97 to 99% with the 16S rRNA sequence from Photobacterium sp., Oceanisphaera sp., Shigella sp., Stenotrophomonas sp, respectively. Mười bảy chủng vi khuẩn đã được phân lập từ 9 mẫu bùn biển từ các vùng ven bờ biển Việt Nam. Bốn chủng vi khuẩn được ghi nhận có khả năng ức chế mạnh sự sinh trưởng và phát triển của các chủng vi khuẩn Staphylococcus aureus ATCC10832, Escherichia coli JM109, và thậm chí cả nấm Fusarium oxysporum. Trình tự gene 16S rRNA của bốn chủng vi khuẩn này đã được khuếch đại bằng PCR sử dụng cặp mồi đặc hiệu. Sản phẩm PCR được nối ghép vào vector pJET1.2 blunt sử dụng T4 ligase, hình thành plasmid tái tổ hợp và biến nạp vào E. coli DH5. Khuẩn lạc có plasmid mang phân đoạn DNA chèn được nuôi cấy và tách plasmid. Trình tự 16S rRNA từ 4 chủng DB1.2, DB1.2.3, DB4.2 and DB5.2 chỉ ra có sự tương đồng 97 ÷ 99% so với trình tự 16S rRNA tương ứng của các chủng vi sinh vật biển trên ngân hàng gene thế giới là Photobacterium sp., Oceanisphaera sp., Shigella sp., và Stenotrophomonas sp., Journal of Vietnamese Environment, Vol 3 No 2 (2012)

International audience; Bioassay-guided fractionation of an extract of leaves of Macaranga kurzii yielded four new compounds, a stilbene (furanokurzin, 1) and three flavonoids (macakurzin A-C, 2-4). Nine known compounds were also isolated (5-13). Their structures were determined by spectroscopic analyses including MS and 2D NMR. The isolates were all evaluated for acetylcholinesterase inhibitory activity. Compound 6 (trans-3,5-dimethoxystilbene) exhibited the greatest activity (IC(50) 9 μM). Cytotoxic evaluation against KB cells showed that compound 7 had an IC(50) of 4 μM, followed by 11 (IC(50) 10 μM) and 3 (IC(50) 13 μM).

International audience; Two new aryl-tetralin lignans, 1 and 2, were isolated from the fruits of Cleistanthus indochinensis by bioassay-guided purification. Their structures were determined by spectroscopic analysis including MS and 2D NMR. The absolute configurations of 1 and 2 were established from examination of their CD spectra. Compound 1 was cytotoxic against KB cells with an IC(50) value of 0.022 μM, while compound 2 had weaker cytotoxicity, with an IC(50) value of 1.4 μM. When tested against other cancer cell lines (MCF-7, MCF-7R, and HT29), 1 showed an IC(50) of 0.014 against MCF-7R cells and an IC(50) of 0.036 μM against MCF-7 cells. A series of amide derivatives of a new lactone, homoderivatives of 1, were prepared. Of these derivatives, only compound 3 had weak cytotoxicity against KB cells.

Bioassay-guided fractionation of the MeOH extract from the stem bark of Neonauclea purpurea used in traditional medicine, resulted in the isolation of 2 indole alkaloids, cadambine (1) and alpha-dihydrocadambine (2), as well as a quinolic compound, 2,6-dimethoxy-1,4-benzoquinone (3). Antimalarial activity evaluation showed that compounds 2 and 3 exhibited mild in vitro antimalarial activity against Plasmodium falciparum, the chloroquine-resistant strain K1 with IC50 values of 6.6 and 11.3 microM, respectively. Compounds 1 and 2 showed no cytotoxicity to monkey (Vero) cells, but compound 3 showed weak cytotoxicity with an IC50 value of 1.19 microM.

International audience; Four new steroids, 3-epi-gitingensine (1), N-acetylgitingensine (6), kibalaurifoline (7) and kibalaurifenone (8), along with the known paravallarine (2), 7α-hydroxyparavallarine (3), gitingensine (4), and N-methylgitingensine (5) were isolated from the leaves of Kibatalia laurifolia. Their structures were determined primarily from mass spectrometry and 2D NMR analyses. On the basis of the known absolute configurations of 2 and 4, the absolute configurations of the new compounds were proposed. Due to the structural relationships of compounds 1-8, a biosynthetic pathway was suggested. Compound 2 was cytotoxic to KB cells (IC(50) 12.8 μM), followed by 1 with IC(50) 21.2 μM.

Cleistanone (1) was isolated from the leaves of Cleistanthus indochinensis and features a new type of triterpenoid carbon skeleton. Its structure was confirmed by X-ray diffraction analysis. A plausible biosynthetic pathway was proposed for 1 and is thought to proceed through a Wagner–Meerwein rearrangement. Cleistanone (1) was found to show cytotoxic activity against human oral epidermoid carcinoma KB cells.

International audience; Two new compounds, an isoflavone (1, 6-methoxybarbigerone) and a bipterocarpan (2, pachylobin) were isolated from the grains of Millettia pachyloba (Leguminosae), together with seven known compounds, 5-methoxybarbigerone (3), calopogoniumisoflavone B (4), durmillone (5), jamaicin (6), ichthynone (7), (-)-pisatin (8) and (-)-rotenone (9). The structures were established from spectroscopic analyses, including mass spectrometry and 2D-NMR. Absolute configuration of 2 was proposed based on that of the known compound (-)-pisatine (8). Compounds 1 and 2 exhibited cytotoxicity against KB cells with IC(50) values of 2.0 and 17.6 µM, respectively.

Three new compounds, prepromalabaricone B ( 1 ) and two dimeric acylphenols, giganteones A ( 2 ) and B ( 3 ) were isolated from EtOAc extract of the fruits of Myristica gigantea (Myristicaceae), together with known promalabaricone C ( 4 ), malabaricones A–C ( 5–7 ) and maingayone ( 8 ). The structures were determined by mass and 2D NMR spectral analysis, and the enzymatic synthesis of giganteones A and B was performed from malabaricone C. Both 2 and 3 possess significant cytotoxic activity in vitro against human nasopharynx KB cells.

[Hz])1 18.1 2.55, m 18.2 2.59, dd (6.5, 12.0)1.82, m 1.84, m2 26.0 2.17, m 26.1 2.21, m3 123.4 5.32, br. s 123.5 5.34, br. s4 140.8 140.75 43.2 43.36 75.1 5.59, d (10.0) 75.2 5.76, d (10.5)7 74.1 5.42, d (10.0) 75.5 5.65, d (10.5)8 83.6 83.69 43.6 43.710 40.1 2.62, br. d (11.0) 40.2 2.62, br. d (12.0)11 74.7 5.69, dd (4.0, 12.5) 74.7 5.72, dd (4.0, 13.0)12 35.4 2.23, dd (13.0, 13.0) 35.1 2.27, dd (13.0, 13.0)2.13, dd (4.0, 13.0) 2.15, dd (4.0, 13.0)13 77.5 77.714 42.8 2.89, d (17.0) 42.8 2.84, br. s2.84, d (17.0)15 173.9 173.716 79.0 4.48, d (9.5) 79.0 4.49, d (9.5)4.29, d (9.5) 4.33, d (9.5)17 19.5 1.37, s 19.8 1.43, s18 20.5 1.58, s 20.5 1.59, s19 17.3 1.43, s 17.3 1.48, s20 16.8 1.21, s 16.9 1.27, s1 164.4 164.42 126.0 125.73 150.7 9.20, d (2.0) 150.7 8.95, d (1.5)5 153.8 8.80, dd (2.0, 5.0) 153.5 8.63, dd (1.5, 5.0)6 123.5 7.41, dd (5.0, 8.0) 123.1 7.20, dd (5.0, 8.0)7 136.9 8.25, dt (2.0, 8.0) 136.6 7.97, dt (1.5, 8.0)1 170.7 165.12 20.6 1.79, s 125.53 C150.6 9.20, d (1.5)5 154.0 8.84, dd (1.5, 4.5)6 123.7 7.46, dd (4.5, 8.0)7 137.3 8.28, dt (1.5, 8.0)1 165.1 165.02 125.5 124.73 151.0 9.19, d (1.5) 151.1 8.96, d (1.5)5 duced from their coupling constants (Table 1). Strong spa-154.0 8.84, dd (1.5, 5.0) 153.8 8.67, dd (1.5, 5.0)6 123.7 7.47, dd (5.0, 8.0) 123.2 7.27, dd (5.0, 8.0)7 137.3 8.28, dt (1.5, 8.0) 137.1 8.07, dt (1.5, 8.0)

Two new alkaloids, dehydronitraramine (1) and N-formylmyrionine (2) were isolated from the leaves of Myrioneuron nutans, and their structures were determined from spectroscopic analysis, including mass spectrometry and 2D-NMR spectroscopy. The absolute configuration 8S, 9R, 10S of N-formylmyrionine (2) was established by N-formylation of the known (8S,9R,10S)-myrionine and then comparison of the optical rotation of the natural N-formylmyrionine (2) with that of the semi-synthetic (8S,9R,10S)-N-formylmyrionine. Dehydronitraramine (1) displayed a moderate antiplasmodial activity against Plasmodiumfalciparum with an IC50 value of 16 μM, whereas both 1 and 2 showed a weak cytotoxicity against KB cells.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Two new alkaloids, dehydronitraramine (1) and N-formylmyrionine (2) were isolated from the leaves of Myrioneuron nutans, and their structures were determined from spectroscopic analysis, including mass spectrometry and 2D-NMR spectroscopy. The absolute configuration 8S, 9R, 10S of N-formylmyrionine (2) was established by N-formylation of the known (8S,9R,10S)-myrionine and then comparison of the optical rotation of the natural N-formylmyrionine (2) with that of the semi-synthetic (8S,9R,10S)-N-formylmyrionine. Dehydronitraramine (1) displayed a moderate antiplasmodial activity against Plasmodiumfalciparum with an IC50 value of 16 μM, whereas both 1 and 2 showed a weak cytotoxicity against KB cells.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Two new compounds, a cyclic peptide desmocyclopeptide (1) and a special flavone desmorostratone (2) were isolated from the stem bark of Desmos rostrata, along with two known compounds, desmosdumotins B (3) and C (4). Their structures were established on the basis of the spectral data, including mass spectrometry and 2D NMR. The total synthesis of desmorostratone (2) was performed in order to confirm its structure as well as that of desmosdumotin C (4), which was a tautomeric mixture in the solution. Finally, cytotoxity of these compounds were evaluated. Desmosdumotin C (4) displayed a moderate inhibition activity against KB cell line with an IC50 of 19.2 μM, whereas the other products showed a weak inhibition against the same cell line target.

International audience; Two new alkaloids, desmorostratine (1) and discretine N-oxide (2), were isolated from the stem bark of Desmos rostrata, together with five known alkaloids, discretine (3), dehydrodiscretine (4), pseudocolumbamine (5), predicentrine (6), and aristolactam AII (7). The structures were established on the basis of spectroscopic data, including mass spectrometry and 2D-NMR. Compound 1 was cytotoxic against KB cells (IC(50) 2.4 microM), while 2, 3, and 4 inhibited Plasmodium falciparum (IC(50) of 4.2, 1.6, and 0.9 microM, respectively).

International audience; Two new alkaloids, (5S,9S,10R)-myrionidine (1) and (5S,9S,10R,13S)-myrionamide (2), along with the known schoberine (3), were isolated from the leaves of Myrioneuron nutans (Rubiaceae), and their structures were determined from spectral analysis, including mass spectrometry and 2D NMR. The total asymmetric syntheses of (-)-myrionidine (1), (-)-schoberine (3), their enantiomers as well as their 9-epimers derivatives were performed, allowing the determination of their absolute configuration together with that of myrionamide (2). (-)-Myrionidine (1) and its synthetic enantiomer (18) showed a significant antimalarial activity on Plasmodium falciparum.

A new alkaloid, myrioneurinol ( 1 ), was isolated from the leaves of Myrioneuron nutans and its structure determined from spectral analysis, including mass spectrometry and 2D NMR. Myrioneurinol ( 1 ) presented an unprecedented fused tetracyclic skeleton. The absolute configuration was established by the modified Mosher's method, using ( R )- and ( S )-9-anthrylmethoxyacetic acid (9-AMAA). A plausible biosynthetic pathway starting from l -lysine via Δ-piperideine was proposed for 1 in comparison with nitraramine biosynthesis and related alkaloids.

Two new compounds, a quinoline alkaloid (1) and a 1,4-dioxane derivative (2), were isolated from culture broth of the marine-derived actinomycete Micromonospora sp. (strain G019) by bioassay-guided fractionation. This actinomycete strain was isolated from sediment, collected at Cát Bà Peninsula, Vietnam. The taxonomic identification was achieved by analysis of 16S rRNA gene sequences. On the basis of morphological and phylogenetic evidence, strain G019 was assigned to the genus Micromonospora. The structures of 1 and 2 were established by spectroscopic data analysis, including one- and two-dimensional NMR, and MS. Compound 1 was found to have antibacterial activity against Escherichia coli (MIC: 48 μg/mL), Salmonella enterica (MIC: 96 μg/mL) and Enterococcus faecalis (MIC: 128 μg/mL), while compound 2 showed inhibitory activity against Enterococcus faecalis (MIC: 32 μg/mL) and Candida albicans (MIC: 64 μg/mL).

International audience; Myrionine (1), a new 8beta-alkyl-cis-decahydroquinoline, was isolated from Myrioneuron nutans. Its structure was determined by spectral methods and then confirmed by X-ray analysis and total synthesis. In solution, 1 gives rise to an N-in/N-out equilibrium. The solvent has weak influence on the N-in/N-out ratio for myrionine (1), whereas together with the anions, it plays an important role for myrionine hydrochloride (9) and hydroiodide (10). The two N-in and N-out conformations obtained separately by crystallization of 9 and 10, respectively, were analyzed by X-ray diffraction.

A novel Daphniphyllum alkaloid, daphcalycine (1), was isolated together with known daphnicyclidin D (2) from the stem bark of Daphniphyllum calycinum. The highly condensed polycyclic structure, established by spectral analysis, possessed an unusual framework: a central quinuclidine like tricycle produced by fusion of a piperidine, a tetrahydropyran, and an oxazine ring in turn condensed to surrounding three penta-, one hexa-, and one hepta-membered rings. The relative configuration of 11 carbon stereocenters of 1 was elucidated on the basis of NOESY.

Two new epimeric tricyclic alkaloids, myrioxazines A and B were isolated from the leaves of Myrioneuron nutans and their structures elucidated by spectral analysis (mass spectrometry and 2D NMR). Absolute configurations were determined by total asymmetric synthesis.

A series of febrifugine analogues were designed and synthesized. Antimalarial activity evaluation of the synthetic compounds indicated that these derivatives had a strong inhibition against both chloroquine-sensitive and -resistant Plasmodium falciparum parasites. Many of them were found to be more active than febrifugine hydrochloride. The tested analogues had also a significant cytotoxicity against four cancer cell lines (KB, MCF7, LU1 and HepG2). Among the synthetic analogues, two compounds 17b and 17h displayed a moderate cytotoxicity while they exhibited a remarkable antimalarial activity.

A new, reliable, and convenient protection-free one-pot method for the synthesis of aureusidin (1) is described. The present synthetic approach involves the condensation of 4,6-dihydroxybenzofuranone with 3,4-dihydroxybenzaldehyde in the presence of concentrated HCl to afford aureusidin (1) in good yield with high purity. This procedure offers a short and simple route for the preparation of aureusidin (1), a bioactive natural product from several vegetal species, as well as for synthesis of other aurones.

Two new styryllactones, macrocalactone (1) and 3-deoxycardiobutanolide (2), were isolated from the fruits of Goniothalamus macrocalyx Ban (Annonaceae), together with seven known compounds including four acetogenins, annonacin (3), solamin (4), isoannonacin (5), trans-murisolinone (6), and three other compounds, 7-acetylaltholactone (7), β-caryophyllene-8R,9R-oxide (8) and 2-(2′-hydroxytetracosanoylamino)-octadecane-l,3,4-triol (9). Their structures were determined by spectroscopic and MS analysis. The absolute configuration of I was determined by X-ray crystallographic analysis. The structures of the acetogenins were confirmed by liquid chromatography coupled to a hybrid quadrupole-time of flight mass spectrometer, using post-column lithium infusion. The results were compared with the fragmentation obtained with a hybrid linear trap-orbitrap mass spectrometer. Compound 7 had cytotoxicity against KB, HepG2, Lu, and MCF7 cell lines with IC50 values of 13.1, 23.7, 26.3 and 60.2 μM, respectively, whereas annonacin (3) was selectively active against KB cells (IC50 value of 6.5 μM). The discovery of 3-deoxycardiobutanolide (2) from the fruits of this plant revealed that G. macrocalyx could be a valuable natural resource to obtain this compound as it has been previously reported to have a significant cytotoxicity against different cancer cell lines, especially HL-60 cells.

From the cytotoxic AcOEt extract of the fruits of Myristica maingayi, a Myristicaceae, five new acylphenols (promalabaricones B and C, maingayic acids B and C, and maingayone) were isolated, together with the known malabaricones A–C. The structures were determined from spectral analysis, including mass spectrometry and 2D NMR. The cytotoxicity of the new compounds and that of malabaricones was assessed against KB cells. A biosynthetic pathway for malabaricones, via the corresponding promalabaricones as precursors, is suggested.

We reported previously that Artemisinin (ART), a widely used anti-malarial drug, is an inhibitor of in vitro HCV subgenomic replicon replication. We here demonstrate that ART exerts its antiviral activity also in hepatoma cells infected with full length infectious HCV JFH-1. We identified a number of ART analogues that are up to 10-fold more potent and selective as in vitro inhibitors of HCV replication than ART. The iron donor Hemin only marginally potentiates the anti-HCV activity of ART in HCV-infected cultures. Carbon-centered radicals have been shown to be critical for the anti-malarial activity of ART. We demonstrate that carbon-centered radicals-trapping (the so-called TEMPO) compounds only marginally affect the anti-HCV activity of ART. This provides evidence that carbon-centered radicals are not the main effectors of the anti-HCV activity of the Artemisinin. ART and analogues may possibly exert their anti-HCV activity by the induction of reactive oxygen species (ROS). The combined anti-HCV activity of ART or its analogues with L-N-Acetylcysteine (L-NAC) [a molecule that inhibits ROS generation] was studied. L-NAC significantly reduced the in vitro anti-HCV activity of ART and derivatives. Taken together, the in vitro anti-HCV activity of ART and analogues can, at least in part, be explained by the induction of ROS; carbon-centered radicals may not be important in the anti-HCV effect of these molecules. ispartof: PLoS One vol:8 issue:12 ispartof: location:United States status: published

Bioassay-guided fractionation of the MeOH extract from the stem bark of Neonauclea purpurea used in traditional medicine, resulted in the isolation of 2 indole alkaloids, cadambine (1) and α-dihydrocadambine (2), as well as a quinolic compound, 2,6-dimethoxy-1,4-benzoquinone (3). Antimalarial activity evaluation showed that compounds 2 and 3 exhibited mild in vitro antimalarial activity against Plasmodium falciparum, the chloroquine-resistant strain K1 with IC50 values of 6.6 and 11.3 μM, respectively. Compounds 1 and 2 showed no cytotoxicity to monkey (Vero) cells, but compound 3 showed weak cytotoxicity with an IC50 value of 1.19 μM.

The investigation of several Berkheya species afforded in addition to already known compounds three unusual sesquiterpene hydrocarbons. Together with modhephene and isocomene, a new one is present, its structure being elucidated by spectroscopic methods and by some chemical transformations. All 18 species investigated contain the typical thiophene derivatives, isolated earlier; the patterns of compounds present divide the species into two groups.

The chemical investigation of Chrysothamnus viscidiflorus afforded, in addition to known bisabolene derivatives, elemicin and p -hydroxyacetophenone, two new diterpene acids. Their structures were determined, by spectroscopic methods and some chemical transformations, as ent -labd-8(17),13 E -dien-15-ol-18-oic acid (viscidic acid A) and ent -labd-8(17),13 E -dien-15-acetoxy-18-oic acid (visidic acid B).

An unusual m-hydroxyacetophenone, named viscidone, and three new chroman-4-one derivatives were isolated from Chrysothamnus viscidiflorus ssp. lanceolatus, which also contained a known p-hydroxyacetophenone derivative. Their structures were determined by spectroscopic (1H and 13C NMR, UV, IR and MS) and chemical means.

Besides coumarin, nobiletin, lucidin dimethyl ether and 5,6,7,3′,4′-pentamethoxyflavone, two new highly oxygenated flavones were isolated from Eupatorium coelestinum . Their structures were determined by spectroscopic methods and alkaline degradations as 5,6,7,8,3′,4′,5′ -heptamethoxyflavone and 5,6,7,8,5′-pentamethoxy-3′,4′-methylenedioxyflavone.

Four new prenylated flavonoids, macarindicins I-IV (1-4) together with ten known compounds, broussoflavonol F (5), vedelianin (6), schweinfurthin E (7), vitexin (8), 2″-rhamnosyl vitexin (9), isovitexin (10), (6R,7E,9R)-9-hydroxy-megastigman-4,7-dien-3-one-9-O-β-D-glucopyranoside (11), 6S,9R)-roseoside (12), (6S,9S)-roseoside (13), and bridelionoside B (14) were isolated from the leaves of Macaranga indica. Their structures were determined on the basis of extensive spectroscopic methods, including 1D-, 2D-NMR, and MS data. All the isolated compounds were evaluated for their cytotoxic activities against four human cancer cell lines including KB, MCF-7, HepG-2, and LU. As a result, compound 6 significantly exhibited cytotoxic activity against all tested human cancer cell lines with IC50 values ranging from 4.7 to 11.0 μM. Compounds 2, 5, and 7 showed moderate cytotoxic activity with IC50 values ranging from 7.0 to 38.7 μM.

Four new prenylated flavonoids, macarindicins I-IV (1-4) together with ten known compounds, broussoflavonol F (5), vedelianin (6), schweinfurthin E (7), vitexin (8), 2″-rhamnosyl vitexin (9), isovitexin (10), (6R,7E,9R)-9-hydroxy-megastigman-4,7-dien-3-one-9-O-β-D-glucopyranoside (11), 6S,9R)-roseoside (12), (6S,9S)-roseoside (13), and bridelionoside B (14) were isolated from the leaves of Macaranga indica. Their structures were determined on the basis of extensive spectroscopic methods, including 1D-, 2D-NMR, and MS data. All the isolated compounds were evaluated for their cytotoxic activities against four human cancer cell lines including KB, MCF-7, HepG-2, and LU. As a result, compound 6 significantly exhibited cytotoxic activity against all tested human cancer cell lines with IC50 values ranging from 4.7 to 11.0 μM. Compounds 2, 5, and 7 showed moderate cytotoxic activity with IC50 values ranging from 7.0 to 38.7 μM.