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1.
West Indian Med J ; 56(1): 5-10, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17621837

RESUMO

Epingaione (4-Methyl-1-(5-methyl-2, 3,4,5-tetrahydro-[2,3']bifuranyl-5-yl)-pentan-2-one) was isolated as one of the major lipophilic secondary metabolites from the leaves and stems of Bontia daphnoides L. The compound gave 79.24% and 50.83% anti-proliferation/cytotoxic activity on the human SH-SY5Y neuroblastoma and TE-671 sarcoma cells in vitro at 50 pg/mL, respectively. Epingaione was transformed into eleven derivatives under laboratory conditions using ethanol, some gave greater anti-proliferation/cytotoxic activity on the cancer cell lines tested. One of the derivatives (compound 2) with enhanced cytotoxic activity was elucidated as 5'-Ethoxy-5-methyl-5-(4-methyl-2-oxo-pentyl)-2,3,4,5-tetrahydro-5'H-[2,3']bifuranyl-2'-one. Both epingaione and compound 2 caused an accumulation of arrested or dead SH-SY5Y neuroblastoma in the m-phase of the cell cycle as revealed by the m-phase specific marker KE 67.


Assuntos
Furanos/farmacologia , Myoporaceae , Neuroblastoma/tratamento farmacológico , Pentanonas/farmacologia , Fitoterapia , Sarcoma/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/química , Humanos , Pentanonas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta , Caules de Planta
2.
West Indian med. j ; 56(1): 5-10, Jan. 2007.
Artigo em Inglês | LILACS | ID: lil-471845

RESUMO

Epingaione (4-Methyl-1-(5-methyl-2, 3,4,5-tetrahydro-[2,3']bifuranyl-5-yl)-pentan-2-one) was isolated as one of the major lipophilic secondary metabolites from the leaves and stems of Bontia daphnoides L. The compound gave 79.24and 50.83anti-proliferation/cytotoxic activity on the human SH-SY5Y neuroblastoma and TE-671 sarcoma cells in vitro at 50 pg/mL, respectively. Epingaione was transformed into eleven derivatives under laboratory conditions using ethanol, some gave greater anti-proliferation/cytotoxic activity on the cancer cell lines tested. One of the derivatives (compound 2) with enhanced cytotoxic activity was elucidated as 5'-Ethoxy-5-methyl-5-(4-methyl-2-oxo-pentyl)-2,3,4,5-tetrahydro-5'H-[2,3']bifuranyl-2'-one. Both epingaione and compound 2 caused an accumulation of arrested or dead SH-SY5Y neuroblastoma in the m-phase of the cell cycle as revealed by the m-phase specific marker KE 67.


Assuntos
Humanos , Furanos/farmacologia , Myoporaceae , Neuroblastoma/tratamento farmacológico , Fitoterapia , Pentanonas/farmacologia , Sarcoma/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular , Ensaios de Seleção de Medicamentos Antitumorais , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Furanos/química , Folhas de Planta , Caules de Planta , Pentanonas/química , Proliferação de Células/efeitos dos fármacos
3.
Mol Divers ; 9(1-3): 33-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15789549

RESUMO

Ligusticum chuanxiong Hort., a plant that is frequently used in traditional Chinese medicine, has been studied using HPLC-coupled spectroscopic techniques such as HPLC-UV, HPLC-MS as well as HPLC-NMR. With the aid of these modern spectroscopic techniques, the main constituents, namely senkyunolide A, butylphthalide, neocnidilide and Z-ligustilide, have been characterized and identified. Phthalide dimers, present in smaller amounts, have been identified by HPLC-UV and HPLC-MS analysis and compared with reference compounds. Stereochemical features of some phthalide monomers have been determined by detailed spectroscopic studies for the first time.


Assuntos
Ligusticum/química , Ácidos Ftálicos/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Medicina Tradicional Chinesa , Modelos Moleculares , Ácidos Ftálicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Espectrofotometria Ultravioleta
4.
Fitoterapia ; 75(2): 117-22, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15030914

RESUMO

The phytochemical investigation of the aerial parts of Tribulus terrestris of Bulgarian origin has resulted in the isolation of the novel furostanol saponin 1, named tribol, together with the known spirostanol saponins 2 and 3 and sitosterol glucoside. The structure of tribol was determined as (25R)-furost-5(6)-ene-3beta,16,26-triol-3-O-alpha-rhamnopyranosyl-(1-->2)-[alpha-rhamnopyranosyl-(1-->4)]-beta-glucopyranoside (1) by spectral analysis, including extensive 1D and 2D-NMR experiments.


Assuntos
Fitoterapia , Extratos Vegetais/química , Tribulus , Bulgária , Humanos , Espectroscopia de Ressonância Magnética , Medicina Tradicional , Componentes Aéreos da Planta , Saponinas/química
5.
Chemosphere ; 51(8): 701-6, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12668029

RESUMO

In the present study, the biologically active natural product dibenzyl trisulphide (DTS) which was previously isolated from the sub-tropical shrub Petiveria alliacea was transformed to methyl benzyl sulphonic anhydride (MBSA) using a "one pot" transformation method. The anhydride was evaluated for anti-microbial activities on the bacteria, Bacillus subtilis and Pseudomonas fluorescens and found to be 2.5 fold more effective than the commercial agents isoniazid and ampicillin in inhibiting the growth of B. subtilis, while on P. fluorescens it was 2.5, 5.0 and 10.0 fold more inhibitory than isoniazid, ampicillin and dibenzyl trisulphide, respectively. DTS was inactive on B. subtillis. The MIC value (microgram/spot) found for DTS on the plant pathogenic fungus, Cladosporium cucumerinum was 5.0 microgram/spot, while MBSA gave a value of 0.1 microgram/spot, compared with 1.25 and 0.16 microgram/spot for the commercial agents ketoconazole and nystatin, respectively. On the larval nematode (Meloidogyne incognita) MBSA inflicted 97.72% and 57.47% Abbotts nematicidal activities at 125.0 and 62.5 ppm, respectively, while DTS had no effect at 125.0 ppm. Nematodes which were immobilized by the low concentrations of MBSA were unable to re-activate when exposed to 10.0 ppm picrotoxin, thus suggesting that the anhydride nematicidal activity is independent of the GABA-ergic neurophysiological pathway.MBSA demonstrated a strong dose dependent radicular suppression effect (r=0.984), on the radicles of Latuca sativa germinating seeds. DTS was weakly active.


Assuntos
Compostos de Benzil/farmacologia , Sulfetos/farmacologia , Animais , Bacillus subtilis , Compostos de Benzil/química , Cladosporium , Larva , Nematoides , Controle de Pragas , Pseudomonas fluorescens , Sulfetos/química , Testes de Toxicidade
6.
Planta Med ; 67(8): 732-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11731915

RESUMO

1'-O-Chlorogenoylchlorogenic acid and 1'-O-chlorogenoylneochlorogenic acid, a new type of quinic acid esters, have been isolated, in addition to six known quinic acid esters, rutin, and a mixture of saponins, from the methanol extract of Cussonia barteri Seemann (Araliaceae) leaves collected in Cameroon. Structure determination was achieved by NMR, mass, IR, and UV spectroscopy. All compounds were tested for inhibitory activity on 5-lipoxygenase and cyclooxygenase-1, for antimicrobial activity against Bacillus subtilis, Pseudomonas fluorescens, and Cladosporium cucumerinum, and for haemolytic activity.


Assuntos
Anti-Infecciosos/isolamento & purificação , Araliaceae/química , Ácido Quínico/isolamento & purificação , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Bioensaio , Camarões , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Medicina Tradicional Africana , Estrutura Molecular , Fitoterapia , Folhas de Planta/química , Ácido Quínico/análogos & derivados , Ácido Quínico/química , Ácido Quínico/uso terapêutico , Relação Estrutura-Atividade
7.
Nat Prod Lett ; 15(1): 35-42, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11547421

RESUMO

A new phenolic glucoside gallate, vanillic acid 4-O-beta-D-(6'-O-galloyl) glucopyranoside (1) was isolated from the bark of Terminalia macroptera Guill.et Perr., together with 3,3',4'-tri-O-methylellagic acid (2) and two triterpene glucopyranosyl esters, 24-deoxysericoside (3) and chebuloside II (4). Compounds 2-4, not described previously for this plant, showed antimicrobial activities against Bacillus subtilis, while 3 and 4 possessed haemolytic properties. In both assays 1 was found to be inactive.


Assuntos
Taninos Hidrolisáveis , Rosales/química , Taninos/isolamento & purificação , Ácido Vanílico , Bacillus subtilis/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Análise Espectral , Taninos/química , Taninos/farmacologia
8.
J Nat Prod ; 64(3): 294-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11277742

RESUMO

Two new hydrolyzable tannins, isoterchebulin (1) and 4,6-O-isoterchebuloyl-D-glucose (2), together with six known tannins, 3-8, were isolated from the bark of Terminalia macroptera. Their structures were elucidated by extensive 1D and 2D NMR studies, MS, and chemical transformations. Biological activities of all compounds were evaluated against the snail Biomphalaria glabrata, the bacteria Bacillus subtilis and Pseudomonas fluorescens, the nematode Caenorhabditis elegans, and four cancer cell lines (Hep G2, MCF-7/S, MDA-MB-231, and 5637 cells). All compounds except 3 showed antimicrobial activities against B. subtilis (MIC 8-64 microg/mL), whereas only 1 was active against C. elegans (100 microg/mL) and B. glabrata(LC(100) = 60 microg/mL). 3 and 8 were toxic against 5637 cells with LC(50) = 84.66 and 41.40 microM, respectively.


Assuntos
Glucose/isolamento & purificação , Taninos Hidrolisáveis , Plantas Medicinais/química , Taninos/isolamento & purificação , Árvores/química , África , Animais , Anti-Helmínticos/química , Anti-Helmínticos/isolamento & purificação , Anti-Helmínticos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Biomphalaria/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Glucose/análogos & derivados , Glucose/química , Glucose/farmacologia , Espectroscopia de Ressonância Magnética , Moluscocidas/química , Moluscocidas/isolamento & purificação , Moluscocidas/farmacologia , Pseudomonas fluorescens/efeitos dos fármacos , Taninos/química , Taninos/farmacologia , Tilápia
9.
Phytochemistry ; 55(3): 255-61, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11142852

RESUMO

Extracts of the aerial parts of Viguiera eriophora ssp. eriophora and Viguiera puruana afforded, in addition to known compounds, six new heliangolides and a germacrolide, whose structures were determined by spectral analysis. HPLC analysis and LC NMR experiments revealed the natural occurrence of the compounds in glandular trichomes. The taxonomic relevance of the results is briefly discussed.


Assuntos
Asteraceae/química , Lactonas/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Lactonas/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Sesquiterpenos/química
10.
J Chromatogr A ; 847(1-2): 109-16, 1999 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-10431354

RESUMO

Reversed-phase high-performance liquid chromatographic separation coupled to (structurally informative) spectroscopic methods like NMR and MS and an efficient bioassay have been used to determine the active compounds from a crude fraction of Bacopa monniera. The fraction containing a mixture of saponins with closely related structures was found to show a significant anthelmintic activity against Caenorhabditis elegans (used as a model test organism for determining anthelmintic activity). The activity was correlated to two dammarane type triterpenoidal saponins containing at least three sugar units. The optimization of separation for 1 mg of the crude sample on column and the sensitivity of on-flow one- and two-dimensional NMR experiments to the high-molecular-mass compounds (M(r) 890-930) has been demonstrated.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Plantas Medicinais/química , Saponinas/análise , Animais , Anti-Helmínticos/análise , Anti-Helmínticos/farmacologia , Bioensaio/métodos , Caenorhabditis elegans/efeitos dos fármacos , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Dados de Sequência Molecular , Saponinas/farmacologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-10327597

RESUMO

Ganglioside patterns from crucian carp brain, muscle, and liver as well as liver gangliosides of roach, carp, the cichlid Oreochromis mossambicus, pigeon, dwarf hamster, and calf were comparatively analyzed by high performance thin layer chromatography (HPTLC). To achieve a rapid estimation on potentially interesting ganglioside compounds, electrospray-ionization mass spectrometry (MS) was directly applied to a chloroform/methanol extract of the major TLC band of crucian carp liver. The spectrum, obtained from a few micrograms of this crude biological sample, revealed a series of peaks corresponding to GM4-like monosialoganglioside species. GC-MS analysis revealed hydroxylated fatty acids ranging from 2 h 20 min:0 to 2 h 26 min:0 for the [M'H]- ions of m/z 1061-1145. Collision induced dissociation tandem MS/MS of the major peak with a [M'H]- ion of m/z 1117 demonstrated the presence of N-acetylneuraminic acid as sialic acid compound. The sugar composition was confirmed by GLC as galactose and sialic acid in a 1:1 molar ratio. Thus, the structure of the ion at m/z 1117 is N-acetylneuraminylgalactosylceramide (NeuAc-Gal-Cer) with the long chain base d18:1 and the hydroxylated fatty acid 2 h 24 min:0. The results demonstrate for the first time unambiguously that NeuAc-Gal-Cer is the main ganglioside fraction in fish liver and that electrospray ionization-mass spectrometry (ESI-MS) can be used to elucidate the chemical composition of a ganglioside fraction obtained by convenient extraction of a HPTLC band.


Assuntos
Carpas/fisiologia , Cromatografia em Camada Delgada/métodos , Gangliosídeos/química , Fígado/química , Espectrometria de Massas/métodos , Animais , Aves , Cricetinae , Músculos/química , Distribuição Tecidual
12.
J Nat Prod ; 61(2): 175-8, 1998 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-9548844

RESUMO

Application of both LC-MS and LC-NMR to a partially purified extract of Vernonia fastigiataled to the direct identification of antibacterial sesquiterpene lactones 1-9 without isolation of individual compounds. The rapid structural analysis of both major and minor components of this class of compounds demonstrated the power of structure-guided screening as a complementary method to assay-guided screening.

13.
Planta Med ; 64(5): 479-81, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17253268

RESUMO

A novel C18-polyacetylene, (+)-9( Z),17-octadecadiene-12,14-diyne-1,11,16-triol, has been isolated from the ethyl acetate extract of Cassonia barteri (Araliaceae) leaves collected in Cameroon. The structure determination was achieved by NMR, mass, IR, and UV spectroscopy. The new polyenyne shows antibacterial activity against Bacillus subtilis and Pseudomonas fluorescens, antifungal activity against Cladosporium cucumerinum, moiluscicidal activity against Biomphalaria glabrata at low concentrations, and in addition it possesses haemolytic activity.

14.
Planta Med ; 64(7): 673-4, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17253310

RESUMO

Sesquiterpene lactones 1-5 were isolated for the first time from the ethyl acetate of Vernonia fastigiata (Asteraceae). Compounds 3, 4 and 5 are new, compounds 1 and 2 have been found earlier in other Vernonia species but not in V. fastigiata.

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