RESUMO
BACKGROUND: The Canadian prairie ecosystem presents a rich source of natural products from plants that are subjected to herbivory by grazing mammals. This type of ecological competition may contribute to the production of natural products of interest in cell biology and medical research. We provide the first biological description of the sesquiterpene lactone, pulchelloid A, which we isolated from the prairie plant, Gaillardia aristata (Asteraceae) and report that it inhibits mitosis in human cells. METHODS AND RESULTS: We found that G. aristata (Blanket flower) extracts were cytotoxic to human cell lines and used phenotypic assays to characterize the bioactivity of extracts. Before dying, cells were characterized by a rounded morphology, phospho-histone H3 signals, mitotic spindles, and active Cdk1. By biology-guided fractionation of Gaillardia extracts, we isolated a sesquiterpene lactone named pulchelloid A. We used immunofluorescence microscopy and observed that cells treated with pulchelloid A have phospho-histone H3 positive chromosomes and a mitotic spindle, confirming that they were in mitosis. Treated cells arrest with an unusual phenotype; they enter a prolonged mitotic arrest in which the spindles become multipolar and the chromosomes acquire histone γH2AX foci, a hallmark of damaged DNA. CONCLUSIONS: We propose that pulchelloid A, a natural product present in the prairie plant Gaillardia aristata, delays cells in mitosis. There is a growing body of evidence that a small number of members of the sesquiterpene lactone chemical family may target proteins that regulate mitosis.
Assuntos
Asteraceae/química , Extratos Vegetais/química , Fuso Acromático/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Células HT29 , Humanos , Mitose/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/genéticaRESUMO
The first phytochemical investigation of Polyalthia cinnamomea led to the isolation and identification of two new oxoprotoberberine alkaloids, (-)-(13aS)-polyalthiacinnamines A and B, together with eleven known compounds. The structures of the new compounds were elucidated by extensive spectroscopic methods. The absolute configuration of miliusacunine E and consanguine B was established by X-ray diffraction analysis using Cu Kα radiation and ECD spectra, whereas the absolute configurations of polyalthiacinnamines A and B were established by comparison of their ECD spectra and specific rotations with those of miliusacunine E and consanguine B. Compounds 1-4, 6, and 8 exhibited α-glucosidase inhibitory activities (IC50 values ranging from 11.3 to 57.9 µM) better than a positive control (acarbose, IC50 83.5 µM). Compound 2 also exhibited NO production inhibitory activity with an IC50 value of 24.4 µM (indomethacin, a positive control, IC50 = 32.2 µM).
Assuntos
Alcaloides/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Óxido Nítrico/antagonistas & inibidores , Extratos Vegetais/farmacologia , Polyalthia/química , alfa-Glucosidases/metabolismo , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Camundongos , Modelos Moleculares , Estrutura Molecular , Óxido Nítrico/biossíntese , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Células RAW 264.7 , Relação Estrutura-Atividade , Árvores/químicaRESUMO
Five new compounds-two phloroglucinol benzophenones, garciniacowones F (1) and G (2), and three xanthones, garciniacowones H (3), I (4), and J (5)-together with seven known xanthones (6-12) were isolated from the fresh leaves of Garcinia cowa. Their structures were elucidated by detailed analysis of NMR and MS data. Compounds 1 and 2 are phloroglucinol benzophenones containing a polyprenylated bicyclo[3.3.1]nonane ring system, while compounds 3-5 are rare xanthones having farnesyl (3 and 5) and geranylgeranyl (5) units at C-8. Compounds 1, 3, 4, 7, 8, and 10 exhibited inhibitory effects on NO production in LPS-induced RAW264.7 macrophage cells with IC50 values ranging from 5.4 to 18.6 µM. Compounds 4 and 8 had α-glucosidase inhibitory activities with IC50 values of 15.4 and 11.4 µM, respectively, which were more potent than that of the acarbose control.
Assuntos
Garcinia/química , Floroglucinol/química , Xantonas/química , alfa-Glucosidases/metabolismo , Animais , Benzofenonas/química , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Folhas de Planta/química , Células RAW 264.7 , alfa-Glucosidases/químicaRESUMO
The chromatographic separation of the components of the acetone extract of Mallotus philippensis fruits yielded five new phenolic compounds including two chalcones, 1 and 3, a functionalized phloroglucinol, 2, two flavanones, 4 and 5, and six known compounds. The structures of 1-5 were confirmed by NMR and mass analyses. Racemic compounds 1 and 2 were separated by chiral-phase HPLC, and the absolute configuration of (+)-1 was confirmed by X-ray diffraction studies and ECD spectroscopic data. The configurations of the enantiomers of 2 were defined by comparison of its ECD data with those of (+)-1. Compounds 6 and 7 exhibited significant antibacterial activities, with MIC values ranging from 3.8 to 15.5 µM.
Assuntos
Antibacterianos/farmacologia , Frutas/química , Mallotus (Planta)/química , Fenóis/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Estrutura Molecular , Fenóis/química , Fenóis/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , EstereoisomerismoRESUMO
A chemical investigation of leaf and root extracts of Millettia extensa led to the isolation and structural elucidation of four new prenylated isoflavones, millexatins G-J (1-4), and three new coumaronochromones, millexatins K-M (5-7), along with 16 known compounds. The structures of the new compounds were determined on the basis of NMR and MS data. Compound 4 is a rare isoflavone having a 2-hydroxyethyl moiety at C-8, whereas the structures of compounds 5-7 formally arise from a ring closure through HO-2' and C-2. The absolute configurations at the C-2 and C-3 positions of 5 and 6 were determined from their ECD spectra through comparison with those of previously reported compounds. Most of compounds were evaluated for their inhibitory effects against nitric oxide (NO) production on RAW264.7 macrophages and their antibacterial activities. Compounds 18 and 19 inhibited NO production with IC50 values of 8.5 and 14.3 µM, respectively. Compounds 13 and 14 showed antibacterial activity against various Gram-positive bacteria with MIC values ranging from 2 to 8 µg/mL.
Assuntos
Antibacterianos/farmacologia , Cromonas/farmacologia , Isoflavonas/farmacologia , Millettia/química , Óxido Nítrico/antagonistas & inibidores , Animais , Isoflavonas/química , Camundongos , Testes de Sensibilidade Microbiana , Óxido Nítrico/biossíntese , Prenilação , Células RAW 264.7RESUMO
Five new aristolactam alkaloids (1-5), dasymaschalolactams A-E, and the first isolation of dasymaschalolactone (17) as a natural product, together with 19 known compounds (6-16 and 18-25) were isolated from the twig extract of Dasymaschalon dasymaschalum. Their structures were elucidated by spectroscopic methods as well as comparisons made from the literature. Compounds 20 and 21 showed α-glucosidase inhibitory activities with IC50 values of 4.5 and 24.7 µM, respectively.
Assuntos
Annonaceae/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Lactamas/química , Lactamas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Caules de Planta/químicaRESUMO
The first phytochemical investigation of the stem extract of Millettia extensa resulted in the isolation and identification of six new isoflavones, millexatins A-F (1-6), together with 16 known compounds. The structures of these new compounds were determined on the basis of their spectroscopic data. Millexatin A (1) is a rare isoflavone containing three isoprenyl units on a modified A ring. Compounds 1, 6, 10, 11, and 14 displayed promising antibacterial activity with MIC values of 2-8 µg/mL.
Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Fabaceae/química , Isoflavonas/química , Isoflavonas/farmacologia , Millettia/química , Caules de Planta/química , Bactérias/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , PrenilaçãoRESUMO
Nahuoic acids A-E (1-5) have been isolated from laboratory cultures of a Streptomyces sp. obtained from a tropical marine sediment. The structures of the new polyketides 2-5 were elucidated by analysis of spectroscopic data of the natural products and the chemical derivatives 6 and 7. Nahuoic acids 1-5 are in vitro inhibitors of the histone methyltransferase SETD8, and nahuoic acid A (1) and its pentaacetate derivative 8 inhibit the proliferation of several cancer cells lines in vitro with modest potency. At the IC50 for cancer cell proliferation, nahuoic acid A (1) showed selective inhibition of SETD8 in U2OS osteosarcoma cells that reflect its selectivity against a panel of pure histone methyl transferases. A cell cycle analysis revealed that the cellular toxicity of nahuoic acid A (1) is likely linked to its ability to inhibit SETD8 activity.
Assuntos
Antineoplásicos/química , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histonas/química , Policetídeos/química , Policetídeos/farmacologia , Streptomyces/química , Antineoplásicos/farmacologia , Linhagem Celular , Proliferação de Células , Sedimentos Geológicos , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/química , Humanos , Estrutura Molecular , Policetídeos/isolamento & purificaçãoRESUMO
Five new xanthones, garciniacowones A-E (1-5), together with 14 known xanthones, 6-19, were isolated from the young fruits and fresh flowers of Garcinia cowa. The structures of 1-5 were elucidated by analysis of their 1D and 2D NMR spectra and mass spectrometric data. The compounds 1-19 were tested in vitro for their antimicrobial activity and for their ability to inhibit α-glucosidase. Compounds 16 and 17 showed the most potent α-glucosidase inhibitory activity, with IC50 values of 7.8 ± 0.5 and 8.7 ± 0.3 µM, respectively. Compounds 8, 9, and 19 showed antibacterial activity against Bacillus subtilis TISTR 088 with identical MIC values of 2 µg/mL, while 8, 10, and 19 exhibited antibacterial activity against Bacillus cereus TISTR 688 with identical MIC values of 4 µg/mL.
Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Garcinia/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Xantonas/isolamento & purificação , Xantonas/farmacologia , alfa-Glucosidases/efeitos dos fármacos , Antibacterianos/química , Bacillus cereus/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Flores/química , Frutas/química , Inibidores de Glicosídeo Hidrolases/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Prenilação , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Tailândia , Xantonas/químicaRESUMO
Two rare new natural products, the neocaged-xanthone pruniflorone T (1) and the rearranged caged-xanthone pruniflorone U (3), and the known caged-xanthone cochinchinone C (2) were isolated from the roots of Cratoxylum formosum ssp. pruniflorum. The unique structures of 1-3 were determined by analysis of NMR and X-ray diffraction data. The X-ray data of 1-3 revealed that they all exist with both enantiomers in their crystal packing. Separation of 1-3 by chiral HPLC led to the isolation of three pairs of enantiomers, (-)-1/(+)-1, (-)-2/(+)-2, and (-)-3/(+)-3, and their absolute configurations were determined by analysis of single-crystal X-ray diffraction and ECD spectroscopic data. A 1:1 mixture of 1 and 3 showed potent in vitro cytotoxicity against an MCF-7 human breast cancer cell line with an IC50 value of 0.11 µg/mL.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Clusiaceae/química , Xantonas/isolamento & purificação , Xantonas/farmacologia , Antineoplásicos Fitogênicos/química , Camptotecina/farmacologia , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Concentração Inibidora 50 , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Estereoisomerismo , Tailândia , Xantonas/químicaRESUMO
Four new carbazole alkaloids, clausenawallines C-F (1-4), along with 18 known compounds (5-22) were isolated from the roots of Clausena wallichii. Compounds 3, 9, and 22 exhibited significant antibacterial activity against methicillin-resistant Staphylococcus aureus SK1 (MRSA SK1) and Staph. aureus TISTR 1466 with MIC values in the range 4-16 µg/mL, whereas compound 4 showed the highest cytotoxicity against oral cavity cancer (KB) and small-cell lung cancer (NCI-H187) with IC(50) values of 10.2 and 4.5 µM, respectively.
Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Carbazóis/isolamento & purificação , Carbazóis/farmacologia , Clausena/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Alcaloides/química , Antibacterianos/química , Antineoplásicos Fitogênicos/química , Carbazóis/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Staphylococcus aureus/efeitos dos fármacos , TailândiaRESUMO
THE TITLE COMPOUND KNOWN AS GLYCOZOLIDAL (SYSTEMATIC NAME: 2,7-dimeth-oxy-9H-carbazole-3-carbaldehyde), C(15)H(13)NO(3), is a naturally occurring carbazole, which was isolated from the roots of Clausena lansium. The carbazole ring system is essentially planar, with an r.m.s. deviation of 0.0093â (1)â Å. In the crystal, inter-molecular N-Hâ¯O hydrogen bonds connect the mol-ecules into a chain along the c axis. C-Hâ¯O, C-Hâ¯π and π-π inter-actions, with centroid-centroid distances of 3.5924â (6), 3.6576â (6) and 3.8613â (6)â Å, are also observed.
RESUMO
The title compound, C(14)H(11)NO(3), was isolated from the roots of Clausena wallichii. The carbazole ring system is approx-imately planar (r.m.s. deviation = 0.039â Å) and the dihedral angle between the two benzene rings is 4.63â (7)°. An intra-molecular O-Hâ¯O hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked into a zigzag network extending parallel to the ac plane by O-Hâ¯N and N-Hâ¯O hydrogen bonds.
RESUMO
Garcinia cowa Roxb. ex Choisy (Clusiaceae) is a Thai local edible plant, which has been used for the treatment of diabetes. The aim of this study is to discover and identify bioactive compounds related to antidiabetic properties from the leaf extract of G. cowa. α-Glucosidase inhibitory bioassay-guided isolation of the ethyl acetate extract of the leaves of G.cowa resulted in the isolation and identification of 11 compounds. Of these, a decahydro-1H-xanthene derivative, garciniacowone K (1), was identified as a novel compound. Their structures were characterized by spectroscopic data and by comparison of their NMR spectroscopic data with those previously reported. All compounds were evaluated for their α-glucosidase inhibitory and glucose consumption activities. Compound 2 showed the highest efficacy in inhibiting α-glucosidase enzyme and promoting glucose consumption activity by 3T3-L1 cells, with IC50 values of 0.5 µM and 13.1 µM, respectively, without causing toxicity to cells.
RESUMO
The essential oils of the fresh rhizomes; flowers; and leaves of Zingiber kerrii Craib were investigated using different extraction techniques; including solid-phase microextraction (SPME), hydrodistillation (HD), and organic solvent (OS), and characterized by gas chromatography-mass spectrometry (GC-MS). A total of 37 SPME; 19 HD; and 36 OS compounds were identified from the rhizome extract of Z. kerrii; with the major components being α-pinene; ß-pinene; and terpinen-4-ol; respectively. From the flower extract; 16 SPME; 2 HD; and 10 OS compounds were identified; (E)-caryophyllene was found as a major compound by these techniques. The leaf extract exhibited 20 SPME; 13 HD; and 14 OS compounds; with α-pinene; (E)-caryophyllene; and n-hexadecanoic acid being the major compounds; respectively. The rhizome extract showed tyrosinase inhibitory activity of 71.60% and a total phenolic content of 22.4 mg gallic acid/g. The IC50 values of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays were 25.2 µg/mL and 153.6 µg/mL; respectively; and the ferric ion reducing antioxidant power (FRAP) assay value was 318.5 µM ascorbic acid equivalent (AAE)/g extract. The rhizome extract showed weak antibacterial activity. This extract showed no adverse toxicity in human keratinocyte (HaCaT) cell lines at concentrations below 200 µg/mL.
Assuntos
Antibacterianos/química , Antioxidantes/química , Inibidores Enzimáticos/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Óleos Voláteis/química , Zingiberaceae/química , Agaricales/enzimologia , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Linhagem Celular , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Flores/química , Humanos , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Folhas de Planta/química , Rizoma/químicaRESUMO
A new 2-arylbenzofuran, spathobenzofuran (1), together with ten known compounds including a 2-arylbenzofuran, three pterocarpans and six isoflavones were isolated from the acetone crude extract of the stems of Spatholobus parviflorus. All compounds were characterised by spectroscopic methods. Compound 4 was active (MIC 8 µg/mL) against Gram-negative Pseudomonas aeruginosa TISTR 781 while compound 2 had modest activity against Gram-positive Staphylococcus aureus TISTR 1466 with a MIC value of 16 µg/mL. All isolated compounds showed no cytotoxicity against Vero and KB cells.
Assuntos
Antibacterianos/isolamento & purificação , Citotoxinas/isolamento & purificação , Fabaceae/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Caules de Planta/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Chlorocebus aethiops , Citotoxinas/química , Citotoxinas/farmacologia , Furanos/isolamento & purificação , Humanos , Isoflavonas/isolamento & purificação , Células KB , Testes de Sensibilidade Microbiana , Fenóis/farmacocinética , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Células VeroRESUMO
The genus Curcuma is part of the Zingiberaceae family, and many Curcuma species have been used as traditional medicine and cosmetics in Thailand. To find new cosmeceutical ingredients, the in vitro anti-inflammatory, anti-oxidant, and cytotoxic activities of four Curcuma species as well as the isolation of compounds from the most active crude extract (C. aromatica) were investigated. The crude extract of C. aromatica showed 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity with an IC50 value of 102.3 µg/mL. The cytotoxicity effect of C. aeruginosa, C. comosa, C. aromatica, and C. longa extracts assessed with the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay at 200 µg/mL were 12.1 2.9, 14.4 4.1, 28.6 4.1, and 46.9 8.6, respectively. C. aeruginosa and C. comosa presented apoptosis cells (57.7 3.1% and 32.6 2.2%, respectively) using the CytoTox-ONE™ assay. Different crude extracts or phytochemicals purified from C. aromatica were evaluated for their anti-inflammatory properties. The crude extract of C. aromatica showed the highest potential to inhibit NF-κB activity, followed by C. aeruginosa, C. comosa, and C. longa, respectively. Among the various purified phytochemicals curcumin, germacrone, curdione, zederone, and curcumenol significantly inhibited NF-κB activation in tumor necrosis factor (TNF) stimulated HaCaT keratinocytes. Of all compounds, curcumin was the most potent anti-inflammatory.
Assuntos
Anti-Inflamatórios/química , Antioxidantes/química , Curcuma/química , Extratos Vegetais/química , Curcuma/classificação , Células HaCaT , Humanos , NF-kappa B/metabolismo , Extratos Vegetais/toxicidade , Sesquiterpenos/química , Sesquiterpenos/classificação , Sesquiterpenos/toxicidade , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Nine phenolic compounds isolated from Cratoxylum maingayi and C. cochinchinense were evaluated for anti-malarial activity against Plasmodium falciparum, and for cytotoxic activity against the NCI-H187 (human small cell lung cancer) cancer cell line. Formoxanthone C (3) was found to be the most active against the NCI-H187 cancer cell line, with an IC(50) of 0.22 microg/mL, while vismione B (7) had the highest activity against Plasmodium falciparum, with an IC(50) of 0.66 microg/mL.
Assuntos
Antimaláricos , Antineoplásicos Fitogênicos , Clusiaceae/química , Fenóis , Extratos Vegetais/química , Animais , Antimaláricos/química , Antimaláricos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Clusiaceae/anatomia & histologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenóis/química , Fenóis/farmacologia , Casca de Planta/química , Plasmodium falciparum/efeitos dos fármacos , Carcinoma de Pequenas Células do PulmãoRESUMO
THE TITLE COMPOUND [SYSTEMATIC NAME: 1-meth-oxy-2-(3-methyl-but-2-en-yl)-9H-carbazole-3-carbaldehyde], C(19)H(19)NO(2), is a natural carbazole which was isolated from the twigs of Clausena lansium. The carbazole ring system is essentially planar with a mean deviation of 0.0068â (10)â Å. The aldehyde substituent is approximately co-planar with the attached benzene ring with a torsion angle of -8.58â (14)°, whereas the meth-oxy group is rotated out of the benzene plane with a torsion angle of -82.17â (11)°. The dihedral angle between the mean planes of the 3-methyl-2-butenyl group and the carbazole ring is 88.06â (5)°. An inter-molecular N-Hâ¯O inter-action connects the mol-ecules into a chain along the a axis. The crystal is further consolidated by a C-Hâ¯O hydrogen bond and two π-π inter-actions with centroid-centroid distances of 3.6592â (6) and 3.7440â (6)â Å.
RESUMO
Four new compounds (1-4) together with six known compounds (5-10) were isolated from the leaf extract of Garcinia nigrolineata. Compound 4 is a rare tocotrienol quinone dimer. The structures were elucidated based on NMR and MS data. All isolated compounds were evaluated for their antibacterial activities.