RESUMO
Assay-guided fractionation of an antitubercular extract obtained from Lessonia nigrescens yielded the phytosterol saringosterol as its active component. No appreciable toxicity against Vero cells was observed for this compound. Saringosterol was also synthesized by oxidation of fucosterol. The MIC values for antitubercular activity of saringosterol and its 24S and 24R epimers were determined as 0.25, 1, and 0.125 microg/mL.
Assuntos
Antituberculosos/isolamento & purificação , Mycobacterium tuberculosis/efeitos dos fármacos , Phaeophyceae/química , Estigmasterol/análogos & derivados , Estigmasterol/isolamento & purificação , Animais , Antituberculosos/síntese química , Antituberculosos/química , Antituberculosos/farmacologia , Células Cultivadas/efeitos dos fármacos , Chile , Chlorocebus aethiops , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Relação Dose-Resposta a Droga , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Oxirredução , Estereoisomerismo , Estigmasterol/síntese química , Estigmasterol/química , Estigmasterol/farmacologia , Células Vero/efeitos dos fármacosRESUMO
Viscidone (0.5%), vanillin, 3',4'-(methylendioxy)acetophenone, 3-ethoxy-4-methoxybenzaldehyde, cinnamic acid, 3-methoxy-4-hydroxymethyl ester were isolated from propolis of hives from Cuncumen. This is the first report on propolis composition of an arid and a Mediterranean type climate area.
Assuntos
Própole/química , Animais , Abelhas , Benzaldeídos/análise , Chile , Cinamatos/análise , Clima , Pólen/química , Própole/isolamento & purificaçãoRESUMO
Pinocembrin, acacetin, galanguin, izalpin, kaempferide, prenyletin and diarytheptane were isolated from propolis from Central Chile.
Assuntos
Fenóis/isolamento & purificação , Própole/química , Animais , Abelhas , Chile , Espectroscopia de Ressonância Magnética , Fenóis/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas de Bombardeamento Rápido de ÁtomosRESUMO
Assay-guided fractionation of the antitubercular MeOH-CH(2)Cl(2) extract obtained from Lippia turbinata led to the isolation of four novel triterpenoids-3beta,25-epoxy-3alpha,21alpha-dihydroxy-22beta-(3-methylbut-2-en-1-oyloxy)olean-12-ene-28-oic acid (1); 3beta,25-epoxy-3alpha,21alpha-dihydroxy-22beta-angeloyloxyolean-12-ene-28-oic acid (2); 3beta,25-epoxy-3alpha,21alpha-dihydroxy-22beta-tigloyloxyolean-12-ene-28-oic acid (3); and 3beta,25-epoxy-3alpha-hydroxy-22beta-(2-methylbutan-1-oyloxy)olean-12-ene-28-oic acid (4)-together with the known triterpenoids lantanilic acid (5), camaric acid (6), lantanolic acid (7), and rehmannic acid (8). The MIC values of 1-8 for growth inhibition of Mycobacterium tuberculosis were determined in the radiorespirometric BACTEC system.
Assuntos
Antituberculosos/farmacologia , Plantas Tóxicas/química , Triterpenos/farmacologia , Animais , Antituberculosos/química , Antituberculosos/toxicidade , Chile , Chlorocebus aethiops , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Triterpenos/química , Triterpenos/toxicidade , Células VeroRESUMO
Propolis from central Chile was investigated for its plant origin by microscopical analysis of pollen grains and leaf fragments found in the sample. The pollen grains that appear with significant higher frequency in the sample corresponded to four native and two introduced species, whereas leaf fragments corresponded to four native species. Seventeen phenolic compounds that belong to the phenylpropane, benzaldehyde, dihydrobenzofuran, or benzopyran classes, were isolated from an organic extract that was found to have a moderate growth inhibitory activity against Mycobacterium avium, M. tuberculosis, and two strains of Staphylococcus aureus. The components responsible for activity were determined.
Assuntos
Derivados de Benzeno/química , Mycobacterium avium/efeitos dos fármacos , Fenóis/química , Plantas/química , Própole/química , Staphylococcus aureus/efeitos dos fármacos , Animais , Abelhas , Derivados de Benzeno/isolamento & purificação , Derivados de Benzeno/farmacologia , Chile , Testes de Sensibilidade Microbiana , Mycobacterium avium/crescimento & desenvolvimento , Fenóis/isolamento & purificação , Fenóis/farmacologia , Folhas de Planta , Pólen , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
Four taraxastane triterpenes, 3 beta-acetoxy-6 beta-hydroxytaraxasta-20-ene, 6 beta-hydroxytaraxasta-20-en-3-one, 6 beta-hydroxytaraxasta-20-ene 3 beta-palmitate and 3 beta,6 beta-dihydroxytaraxasta-20-ene were isolated from the dichloromethane-methanol extract of Chuquiraga ulicina ssp. ulicina together with the known triterpenes lupeol, lupenyl acetate, lupenone, friedelinol, 3 beta-acetoxy-30-nor-lupan-20-one, and 30-nor-lupan-3 beta-ol-20-one.
Assuntos
Extratos Vegetais/química , Plantas Medicinais , Triterpenos/química , Chile , Clima Desértico , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Espectrometria de Massa de Íon Secundário , Triterpenos/isolamento & purificaçãoRESUMO
The flavonoids 5-hydroxy-7-methoxyflavanone, 6,8-dimethyl-5,7-dihydroxyflavanone and 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone, a mixture of alkyl esters of p-coumaric acid, the triterpenoids oleanolic acid and maslinic acid, the monoterpenoid 1 alpha,2 beta,4 beta-trihydroxy-p-menthane, the sesquiterpenoid clovandiol and beta-sitosterol were isolated from the aerial parts of Luma gayana (Barn.) Burret. This is the first report on the chemistry of this species.
Assuntos
Flavonoides/química , Plantas Medicinais , Terpenos/química , Chile , Flavonoides/isolamento & purificação , Medicina Tradicional , Estrutura Molecular , Terpenos/isolamento & purificaçãoRESUMO
Screening of plants from South America for antitubercular activity and subsequent assay-guided fractionation resulted in the isolation and characterization of several pentacyclic triterpenoids. The MIC values of 22 triterpenoids were determined using the radiorespiratory BACTEC assay and range from 8 microM to above 128 microM. The structure-activity relationships are discussed.
Assuntos
Antituberculosos/isolamento & purificação , Antituberculosos/farmacologia , Plantas Medicinais/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Antituberculosos/química , Argentina , Chile , Relação Dose-Resposta a Droga , Técnicas In Vitro , Medicina Tradicional , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Relação Estrutura-Atividade , Triterpenos/químicaRESUMO
Bioactivity-guided fractionation of the petroleum ether extract of Azorella madreporica Clos has led to the isolation of the novel, antitubercular mulinane diterpenoid 1. The structure has been elucidated on the basis of its 1D and 2D NMR spectra and by comparison with mulinolic acid 2 and a dehydration product 3 obtained from 1. The MIC of 1 for growth inhibition of the H37Rv strain of Mycobacterium tuberculosis was determined as 20 microg/mL. LC-MS and NMR have suggested the presence of this new compound in four other species of Azorella.
Assuntos
Antituberculosos/isolamento & purificação , Diterpenos/isolamento & purificação , Mycobacterium tuberculosis/efeitos dos fármacos , Plantas Medicinais/química , Antituberculosos/farmacologia , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Conformação Molecular , Dados de Sequência Molecular , América do SulRESUMO
Three new (1, 3, 4) and two known lignans (2 and 5) were isolated from Chilean propolis. Compound 1 was identified as a trimeric coniferyl alcohol acetate and 3 as the diastereomer of the dimeric coniferyl alcohol acetate 2. Compound 4 was identified as a dihydrobenzofuran lignan aldehyde, which was isolated together with the related known acetate 5.
Assuntos
Lignanas/isolamento & purificação , Própole/química , Chile , Lignanas/química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
Eight urs-12-ene triterpenoids, beta-sitosterol, (+)-catechin, and apigenin 7-O-glucoside were isolated from the leaves of Acaena pinnatifida R. et P. The triterpenoids were characterized as pomolic acid, pomolic acid-3-acetate, tormentic acid, 2-epi-tormentic acid, euscaphic acid, tormentic acid glucoside, niga-ichigoside F1, and niga-ichigoside F2.