RESUMO
A new lactone, 7-epi-griffonilide (1), and six known compounds, 2, 3a - 3c, 4a and 4b, were isolated from the leaves of Bauhinia pentandra (Fabaceae). The structures elucidation of 1 and 2 were based on detailed 2D NMR techniques and spectral comparison with related compounds, leading to complete assignment of the 1H and 13C NMR spectra.
Assuntos
Bauhinia/química , Lactonas/química , Lactonas/isolamento & purificação , Folhas de Planta/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética/métodos , Valores de Referência , EstereoisomerismoRESUMO
Biflorin 1 is a biologically active quinone, isolated from Capraria biflora. Five new biflorin-based nitrogen derivatives were synthesized, of which two were mixtures of (E)- and (Z)- isomers: (Z)-2a, (Z)-2b, (Z)-3a, (Z)- and (E)-3b, (Z)- and (E)-3c. The antibacterial activity was investigated using the microdilution method for determining the minimum inhibitory concentration (MIC) against six bacterial strains. Tests have shown that these derivatives have potential against all bacterial strains. The cytotoxic activity was also evaluated against three strains of cancer cells, but none of the derivatives showed activity.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Hidrazonas/farmacologia , Naftoquinonas/farmacologia , Oximas/farmacologia , Scrophulariaceae/química , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Testes de Sensibilidade Microbiana , Naftoquinonas/síntese química , Naftoquinonas/química , Neoplasias/tratamento farmacológico , Oximas/síntese química , Oximas/químicaRESUMO
BACKGROUND: Bauhinia pentandrais popularly known as "mororó" and inhabits the Caatinga and Savannah biomes. OBJECTIVE: This paper reports the chemical composition of the essential and fatty oils of the leaves from B. pentandra. MATERIALS AND METHODS: The essential oil was obtained by hydrodistillation and the fixed oil by extraction with hexane, followed by saponification with KOH/MeOH, and methylation using MeOH/HCl. The constituents were analyzed by gas chromatography-mass spectrometry. RESULTS: The major constituent of the essential oil was the phytol (58.78% ±8.51%), and of the fatty oil were palmitic (29.03%), stearic (28.58%) and linolenic (10.53%) acids. CONCLUSION: Of the compounds identified in the essential oil, three are first reported in this species, and this is the first record of the chemical composition of the fixed oil.
RESUMO
In order to develop bioactive lithocholic acid derivatives, we prepared fifteen semi-synthetic compounds through modification at C-3 and/or C-24. The reactions showed yields ranging from 37% to 100%. The structures of all compounds obtained were identified on the basis of their spectral data (IR, MS, 1D- and 2D-NMR). The activity of lithocholic acid and derivatives was evaluated against the growth of Escherichia coli, Staphylococcus aureus, Bacillus cereus and Pseudomonas aeruginosa. The derivative 3α-formyloxy-5ß-cholan-24-oic acid (LA-06) showed the best activity, with MIC values of 0.0790 mM against E. coli (Ec 27) and B. cereus in both cases, and 0.0395 mM against S. aureus (ATCC 12692). Lithocholic acid and the derivatives with MIC⩽1.2 mM were evaluated on the susceptibility of some bacterial pathogens to the aminoglycoside antibiotics neomycin, amikacin and gentamicin was evaluated. There are no previously reported studies about these compounds as modifiers of the action of antibiotics or any other drugs.
Assuntos
Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Ácido Litocólico/análogos & derivados , Ácido Litocólico/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Bacillus cereus/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Escherichia coli/crescimento & desenvolvimento , Ácido Litocólico/síntese química , Ácido Litocólico/química , Testes de Sensibilidade Microbiana , Conformação Molecular , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Relação Estrutura-AtividadeRESUMO
ABSTRACT A new lactone, 7-epi-griffonilide (1), and six known compounds, 2, 3a - 3c, 4a and 4b, were isolated from the leaves of Bauhinia pentandra (Fabaceae). The structures elucidation of 1 and 2 were based on detailed 2D NMR techniques and spectral comparison with related compounds, leading to complete assignment of the 1H and 13C NMR spectra.