RESUMO
Three new Myrioneuron alkaloids, myrifamines A-C (1-3), with unique skeletons were isolated from Myrioneuron faberi. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis, and the stereochemistry of the other two alkaloids was determined using a combination of ROESY experiments and calculated and experimental electronic circular dichroism spectra. Myrifamine C (3) is the first example of a symmetric dimer among the Myrioneuron alkaloids. Known alkaloids myrionamide (4) and schoberine (5) were also isolated, and experimental NMR and X-ray diffraction data suggest their structural revision. Compound 2 showed significant inhibitory activity toward the hepatitis C virus in vitro, with a therapeutic index (CC50/EC50) greater than 108.7.
Assuntos
Alcaloides/isolamento & purificação , Antivirais/isolamento & purificação , Rubiaceae/química , Alcaloides/química , Alcaloides/farmacologia , Antivirais/química , Antivirais/farmacologia , Cristalografia por Raios X , Hepacivirus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Quinolinas/químicaRESUMO
One Myrioneuron alkaloid, myrifabine (1), the first example of a dimer with 12 chiral centers embraced in a decacyclic novel skeleton, was isolated from Myrioneuron faberi . Its structure was elucidated by spectroscopic data and single-crystal X-ray diffraction. The antimicrobial and cytotoxic activities of 1 were evaluated in vitro.
Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Anti-Infecciosos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Rubiaceae/química , Alcaloides/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Staphylococcus aureus/efeitos dos fármacos , Vancomicina/farmacologiaRESUMO
AIM: To study the Amaryllidaceae alkaloids of the bulbs of Lycoris radiata. METHODS: The chemical constituents were isolated and purified by various chromatographic techniques, and the chemical structures were elucidated on the basis of spectroscopic methods. In addition, the antiviral activities of alkaloids 1-10 were evaluated using flu virus A. RESULTS: One new homolycorine-type alkaloid 2α-methoxy-6-O-ethyloduline (1), together with nine known alkaloids 2α-methoxy-6-O-methyloduline (2), trispherine (3), 8-O-demethylhomolycorine (4), homolycorine (5), 9-O-demethylhomolycorine (6), oduline (7), lycorenine (8), 6α-O-methyllycorenine (9) and O-ethyllycorenine (10) were obtained. CONCLUSION: Alkaloid 1 is a new compound, and 1-3 were major alkaloids in this plant. Alkaloids 1-3 showed weak antiviral activities against flu virus A with IC50 values of 2.06, 0.69, and 2.71 µg·mL-1 and CC50 values of 14.37, 4.79, and 80.12 µg·mL-1, respectively.
Assuntos
Alcaloides/química , Flores/química , Lycoris/química , Extratos Vegetais/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologiaRESUMO
Myriberine A (1) possessing an unprecedented carbon skeleton was isolated from Myrioneuron faberi. The structure and absolute configuration of 1 were elucidated by a combination of spectroscopic data, X-ray crystallographic, and computational methods. Myriberine A (1) demonstrated inhibition against the hepatitis C virus (HCV) life cycle in vitro.