RESUMEN
A methanol extract of the wood of Diospyros burmanica, collected in Burma (Myanmar), was found to exhibit significant activity against Leishmania major. Subsequent chromatographically resolved fractionation led to the isolation of three novel bisnaphthoquinone analogues, burmanin A, B, and C (1-3), together with nine known compounds (4-12). The structure of 1 was confirmed by X-ray crystallography, and those of 2 and 3 by spectroscopic techniques, including 1D and 2D NMR. The inhibitory activities of the isolates were evaluated against the promastigote forms of Leishmania major and the murine macrophage-like cell line, RAW264.7.
Asunto(s)
Antiprotozoarios/farmacología , Diospyros/química , Leishmania major/efectos de los fármacos , Naftoles/farmacología , Naftoquinonas/farmacología , Animales , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Leishmania major/metabolismo , Ratones , Modelos Moleculares , Estructura Molecular , Mianmar , Naftoles/química , Naftoles/aislamiento & purificación , Naftoquinonas/química , Naftoquinonas/aislamiento & purificación , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/química , Estereoisomerismo , Relación Estructura-Actividad , Madera/químicaRESUMEN
A methanol extract of the wood of Cordia fragrantissima, collected in Burma (Myanmar), was found to exhibit significant activity against Leishmania major. Bioassay-guided fractionation of this extract using several chromatographic techniques afforded three new compounds (1-3) and five known compounds (4-8). The structures of the new compounds were revealed on the basis of spectroscopic data interpretation and by X-ray crystallographic analysis. Interestingly, the new compounds, despite the presence of asymmetric carbons, were found to be racemates. The activities of the isolates from C. fragrantissima and several derivatives were evaluated against the promastigote forms of Leishmania major, L. panamensis, and L. guyanensis.
Asunto(s)
Antiprotozoarios/aislamiento & purificación , Antiprotozoarios/farmacología , Cordia/química , Hidroquinonas/aislamiento & purificación , Hidroquinonas/farmacología , Leishmania/efectos de los fármacos , Plantas Medicinales/química , Animales , Antiprotozoarios/química , Cristalografía por Rayos X , Hidroquinonas/química , Leishmania/crecimiento & desarrollo , Conformación Molecular , Estructura Molecular , Mianmar , Pruebas de Sensibilidad ParasitariaRESUMEN
Six new sesquiterpenes, (Z)-2beta-hydroxy-14-hydro-beta-santalol (1), (Z)-2alpha-hydroxy-albumol (2), 2R-(Z)-campherene-2,13-diol (3), (Z)-campherene-2beta,13-diol (4), (Z)-7-hydroxynuciferol (5), and (Z)-1beta-hydroxy-2-hydrolanceol (6), together with five known compounds, (Z)-alpha-santalol (7), (Z)-beta-santalol (8), (Z)-lanceol (9), alpha-santaldiol (10), and beta-santaldiol (11), were isolated from Santalum album, by using bioassay-guided fractionation for Helicobacter pylori. The structures were determined by extensive NMR studies. The absolute configuration of compound 3 was determined by a modified Mosher method. The crude extracts as well as the isolated compounds showed antibacterial activity against H. pylori. Especially, compounds 7 and 8 have strong anti-H. pylori activities against a clarithromycin-resistant strain (TS281) as well as other strains.