Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Anal Bioanal Chem ; 414(19): 5929-5942, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35725831

RESUMO

A comprehensive metabolomic strategy, integrating 1H NMR and MS-based multi-block modelling in conjunction with multi-informational molecular networking, has been developed to discriminate sponges of the order Haplosclerida, well known for being taxonomically contentious. An in-house collection of 33 marine sponge samples belonging to three families (Callyspongiidae, Chalinidae, Petrosiidae) and four different genera (Callyspongia, Haliclona, Petrosia, Xestospongia) was investigated using LC-MS/MS, molecular networking, and the annotations processes combined with NMR data and multivariate statistical modelling. The combination of MS and NMR data into supervised multivariate models led to the discrimination of, out of the four genera, three groups based on the presence of metabolites, not necessarily previously described in the Haplosclerida order. Although these metabolomic methods have already been applied separately, it is the first time that a multi-block untargeted approach using MS and NMR has been combined with molecular networking and statistically analyzed, pointing out the pros and cons of this strategy.


Assuntos
Poríferos , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida , Espectroscopia de Ressonância Magnética , Metabolômica/métodos , Poríferos/química
2.
Mar Drugs ; 16(11)2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30388820

RESUMO

Chemical investigation of the methanol extract of the Vietnamese marine sponge Ircinia echinata led to the isolation of six new 9α-hydroxy-5α,6α-epoxysterols: 5α,6α-epoxycholesta-7,22(E)-dien-3ß,9α-diol (1), 5α,6α-epoxycholesta-7,24(28)-dien-3ß,9α-diol (2), (24R)-5α,6α-epoxy-24-ethyl-cholesta-7-en-3ß,9α-diol (3), 5α,6α-epoxycholesta-7-en-3ß,9α-diol (4), (24S)-5α,6α-epoxyergosta-7,22-dien-3ß,9α-diol (5), and (24R)-5α,6α-epoxy-24-methyl-cholesta-7-en-3ß,9α-diol (6) along with the known 5α-6α-epoxysterols: 5α,6α-epoxystigmasta-7-en-3ß-ol (7), 5α,6α-epoxystigmasta-7,22-dien-3ß-ol (8), and 5α,6α-epoxyergosta-7-en-3ß-ol (9). Their structures and their configurations were established on the basis of high resolution mass spectra and extensive 1D and 2D NMR spectroscopic data and by comparison with the literature. Their cytotoxic activity, evaluated against three human cancer cell lines, MCF-7, Hep-G2 and LU-1, revealed that only compounds 3 and 4 exhibited significant antiproliferative activity and compound 3 showed a selective inhibition towards the MCF-7 human breast cancer cells.


Assuntos
Antineoplásicos/farmacologia , Organismos Aquáticos/química , Compostos de Epóxi/farmacologia , Poríferos/química , Esteróis/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Compostos de Epóxi/química , Compostos de Epóxi/isolamento & purificação , Células Hep G2 , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Estrutura Molecular , Esteróis/química , Esteróis/isolamento & purificação , Vietnã
3.
Nat Prod Commun ; 11(1): 79-80, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26996025

RESUMO

A new O-geranylated chalcone, 2'-hydroxy-2-methoxy-4'-O-[(E)-3,7-dimethyl-2,6-octadienyl] chalcone (1), together with three known flavones, 5-hydroxy-7,2'-dimethoxyflavone (2), skullcapflavone I (3) and echioidin (4), were isolated from the leaves of Andrographis lobelioides. The structure of 1 and the known compounds (2-4) were achieved by extensive 1D and 2D NMR spectral and chemical studies.


Assuntos
Andrographis/química , Chalconas/química , Flavonas/química , Estrutura Molecular
4.
Nat Prod Res ; 29(1): 82-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25226549

RESUMO

A new di-C-prenylated coumarin, 7-methoxy-6,8-bis-(2,3-dihydroxy-3-methylbutyl)-coumarin (1), together with seven known compounds, isopimpinellin (2), an arylbenzofuran (3), three flavonoids (4-6), (+)-maackianin (7) and echinoisoflavanone (8), were isolated from the leaves of Sophora interrupta Bedd. The structure of the new compound 1 as well as known compounds was elucidated by extensive 1D and 2D NMR spectral studies.


Assuntos
Cumarínicos/isolamento & purificação , Sophora/química , Cumarínicos/química , Flavonoides/química , Flavonoides/isolamento & purificação , Índia , Isoflavonas/química , Isoflavonas/isolamento & purificação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Prenilação
5.
Chemistry ; 19(48): 16389-93, 2013 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-24136873

RESUMO

A bio-inspired strategy was used to complete the formal synthesis of the antitubercular hirsutellone B and congeners A and C, through construction of its decahydrofluorene core from a linear polyene strand activated at both ends by a silyl enol ether and an allyl acetate. Our synthesis features a key electrophilic cyclization, starting with the remote activation (by [Yb(OTf)3] or BF3·OEt2) of the allyl acetate and stereoselectively affording the C ring. This was followed by an intramolecular Diels-Alder reaction to get the tricyclic core of the natural product. The stereoselective reduction of the resulting ketone towards the formal intermediate was critical to the success of this strategy.


Assuntos
Antituberculosos/síntese química , Produtos Biológicos/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Ácidos de Lewis/química , Antituberculosos/química , Antituberculosos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Ciclização , Reação de Cicloadição , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Hypocreales/química , Cetonas/química , Estrutura Molecular
6.
Nat Prod Res ; 27(20): 1823-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23406166

RESUMO

A new O-prenylated flavonol, 3',4'-dimethoxy-7-(γ,γ-dimethylallyloxy)flavonol (1), together with three known compounds, 2'-hydroxy-3,4-dimethoxychalcone (2), biochanin A (3) and kaempferol-3-O-ß-D-glucopyranoside (4), were isolated from the roots of Sophora interrupta Bedd. The structure of compound 1 was elucidated by extensive 1D and 2D NMR spectral studies.


Assuntos
Flavonóis/isolamento & purificação , Extratos Vegetais/análise , Raízes de Plantas/química , Sophora/química , Flavonóis/química , Hexanos , Índia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Prenilação
7.
Nat Prod Commun ; 7(10): 1305-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23156994

RESUMO

Two new flavonoids, (2S)-3',4',5'-trimethoxyflavanone (1) and 2'-hydroxy-2,4-dimethoxy-4'-O-[(E)-3,7-dimethyl-2,6-octadienyl]chalcone (2), together with a known pterocarpene, flemichapparin B (3), and a known rotenoid, dehydrodeguelin (4), were isolated from the seeds of Derris scandens. Their structures were determined by means of extensive 1D and 2D NMR spectral studies.


Assuntos
Derris/química , Flavanonas/química , Flavonoides/química , Sementes/química , Flavanonas/isolamento & purificação , Flavonoides/isolamento & purificação , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
8.
Planta Med ; 78(5): 459-64, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22271083

RESUMO

Two new polyprenylated acylphloroglucinols, spiranthenones A (1) and B (2), a sesquiterpenoid, 6 α-acetoxy,1 ß-hydroxyeudesm-4(15)-ene (3), along with sesamin and ß-sitosterol, were isolated from the EtOAc extract of the leaves of Spiranthera odoratissima, and shown to display antiprotozoal activity. Their structures and relative stereochemistry were elucidated by NMR and mass spectrometry. These compounds exhibited moderate antiprotozoal activity, but without significant cytotoxicity against fibroblasts cell line NIH-3T3. Compound 3 was the most selective towards parasites.


Assuntos
Antiprotozoários/isolamento & purificação , Floroglucinol/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Rutaceae/química , Animais , Antiprotozoários/química , Antiprotozoários/farmacologia , Brasil , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Leishmania/efeitos dos fármacos , Camundongos , Estrutura Molecular , Floroglucinol/análogos & derivados , Floroglucinol/química , Floroglucinol/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Plantas Medicinais/química , Plasmodium falciparum/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos
9.
Phytochemistry ; 73(1): 65-73, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22033013

RESUMO

Four vobasinyl-iboga bisindole and one 2-acyl monomeric indole alkaloids were isolated from the stem bark of Muntafara sessilifolia along with eleven known compounds. Their structures and relative stereochemistry were elucidated on the basis of spectroscopic data including 1D and 2D NMR and mass spectrometry (MS). All isolated compounds were evaluated in vitro for antiplasmodial activity against the chloroquine-resistant strain FcB1 of Plasmodium falciparum, and for cytotoxicity against the human lung cell line MRC-5 and the rat skeletal muscle cell line L-6. 3'-Oxo-tabernaelegantine A exhibited antiplasmodial activity (4.4 µM IC(50)) associated with non-significant cytotoxicity (selectivity index of 48). Tabernaelegantine B and D displayed the highest cytotoxicity with IC(50) values of 0.47 and 1.89 µM on MRC-5 cells, and 0.42 and 2.7 µM on L-6 cells, respectively.


Assuntos
Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Apocynaceae/química , Alcaloides Indólicos/isolamento & purificação , Alcaloides Indólicos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Terpenos/isolamento & purificação , Terpenos/farmacologia , Animais , Antimaláricos/química , Antineoplásicos Fitogênicos/química , Cloroquina , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Alcaloides Indólicos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Ratos , Terpenos/química
10.
Phytochemistry ; 71(8-9): 1007-13, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20385395

RESUMO

Two clerodane diterpenoids, antadiosbulbins A and B and two 19-norclerodane diterpenes, 8-epidiosbulbins E and G along with the known diosbulbin E as well as nine known phenolics including five phenanthrenes and stilbenes and four flavonoids were isolated from the ethyl acetate soluble part of the methanolic extract of the tubers of Dioscorea antaly, a yam endemic to Madagascar. Structures were determined by analysis of the spectral data, mainly 2D-NMR and mass spectrometry.


Assuntos
Dioscorea/química , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/isolamento & purificação , Madagáscar , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Tubérculos/química
11.
Phytochemistry ; 70(11-12): 1435-41, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19766274

RESUMO

An antiplasmodial bioguided investigation of the EtOAc extract of the aerial parts of Teucrium ramosissimum led to isolation and identification of three sesquiterpenoids, teucmosin, 4alpha-hydroxy-homalomenol C, 1beta,4beta,7alpha-trihydroxy-8,9-eudesmene and two trinorsesquiterpenoids, 4beta-hydroxy-11,12,13-trinor-5-eudesmen-1,7-dione and 1beta,4beta-dihydroxy-11,12,13-trinor-8,9-eudesmen-7-one together with five known sesquiterpenoids, oplopanone, homalomenol C, oxo-T-cadinol, 1beta,4beta,6beta-trihydroxyeudesmane, 1beta,4beta,7alpha-trihydroxyeudesmane and four flavonoids, 5-hydroxy-7,4'-dimethoxyflavone, salvigenin, genkwanin and cirsimaritin. The structures and the relative stereochemistry were elucidated by extensive spectroscopic studies including 1D and 2D NMR and mass spectrometry (MS). Homalomenol C, 4beta-hydroxy-11,12,13-trinor-5-eudesmen-1,7-dione, oxo-T-cadinol and 1beta,4beta,6beta-trihydroxyeudesmane displayed a significant in vitro antiplasmodial activity against Plasmodium falciparum with IC(50) values ranging from 1.2 to 5.0 microg/ml. Furthermore, no cytotoxicity was observed upon the human diploid lung cell line MRC-5 for these compounds.


Assuntos
Antimaláricos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Plasmodium falciparum/efeitos dos fármacos , Sesquiterpenos/isolamento & purificação , Teucrium/química , Animais , Antimaláricos/química , Antimaláricos/farmacologia , Linhagem Celular , Humanos , Pulmão/citologia , Pulmão/efeitos dos fármacos , Estrutura Molecular , Componentes Aéreos da Planta , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia
12.
Phytochemistry ; 70(10): 1239-45, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19679323

RESUMO

In the framework of the phytochemical investigation of plant species eaten by wild chimpanzees in their natural environment in Uganda, leaf samples of Markhamia lutea were selected and collected. The crude ethyl acetate extract of M. lutea leaves exhibited significant in vitro anti-parasitic activity and low cytotoxicity against MRC5 and KB cells. Fractionation of this extract led to six cycloartane triterpenoids, musambins A-C and their 3-O-xyloside derivatives musambiosides A-C. The structures were elucidated on the basis of spectral studies including mass spectroscopy and extensive 2D NMR. Most of the compounds exhibited mild anti-leishmanial and anti-trypanosomal activities.


Assuntos
Magnoliopsida/química , Pan troglodytes , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Triterpenos/farmacologia , Animais , Antimaláricos/química , Antimaláricos/farmacologia , Antiprotozoários/química , Antiprotozoários/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Leishmania/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Plasmodium falciparum/efeitos dos fármacos , Triterpenos/química , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos
13.
Nat Prod Commun ; 4(1): 59-62, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19370876

RESUMO

Two new flavanones, (2S)-5-hydroxy-7,4'-di-O-(gamma,gamma-dimethylallyl)flavanone (1) and 6-hydroxy-E-3-(2,5-dimethoxybenzylidine)-2',5'-dimethoxyflavanone (2), together with three known compounds, tephrowatsin C, afrormosin and kaempferol 3-O-beta-D-glucopyranoside were isolated from the roots of Tephrosia calophylla. The structures of 1 and 2 were established by extensive 2D NMR spectral studies.


Assuntos
Flavonas/química , Tephrosia/química , Estrutura Molecular
14.
Planta Med ; 74(4): 417-21, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18484535

RESUMO

Piptadenia pervillei Vatke (Fabaceae) was selected from a screening programme devoted to the search of naturally-occuring antimalarial compounds from plants of Madagascar. Bioassay-guided fractionation of the ethyl acetate extract of the leaves led to the isolation of four phenolic compounds, (+)-catechin ( 1), (+)-catechin 5-gallate ( 2), (+)-catechin 3-gallate ( 3) and ethyl gallate ( 4). Structures were determined by NMR and mass spectroscopy. Compounds 2 and 3 displayed the highest in vitro activity against the chloroquine-resistant strain FcB1 of Plasmodium falciparum with IC (50) values of 1.2 microM and 1.0 microM, respectively, and no significant cytotoxicity against the human embryonic lung cells MRC-5 was measured (IC (50) values > 75 microM). Five analogues ( 5 - 9) of (+)-catechin 5-gallate ( 2) were synthesized and evaluated for their antiplasmodial activity.


Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Fabaceae/química , Fenóis/química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular , Humanos , Estrutura Molecular , Plasmodium falciparum/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...