RESUMEN
A new metabolite, 3,16-diketoaphidicolan (1), was isolated together with four known compounds: aphidicolin (2), 17-acetyl-aphidicolin (3), (+)-eupenoxide (4), and phomoxanthone A (5) from the endophytic fungus Phoma sp. The structure of the new compound 1 was determined by spectroscopic methods (mainly extensive 1D and 2D NMR experiments and by mass spectral measurements) and confirmed by X-ray crystallography. Its absolute configuration was assigned by means of the solid-state CD/TDDFT approach comparing the solid-state CD spectrum with the TDDFT-calculated one on the X-ray geometry.
Asunto(s)
Afidicolina/análogos & derivados , Ascomicetos/metabolismo , Plantas/microbiología , Afidicolina/química , Dicroismo Circular , Cristalografía por Rayos X , Espectroscopía de Resonancia MagnéticaRESUMEN
Eight compounds were isolated from the roots of Garcinia polyantha, and identified. Two of them, the xanthone garciniaxanthone I (1), and the triterpene, named garcinane (2), are reported as new natural products. The structures of the new compounds were elucidated on the basis of 1D and 2D NMR spectroscopic studies. The structure of compound 1 was confirmed by X-ray crystallography. Among the remaining six known compounds, three were known xanthones [smeathxanthone A (3), smeathxanthone B (4), and chefouxanthone (5)], one benzophenone [isoxanthochymol (6)], one triterpene [magnificol], and one sterol [beta-sitosterol]. The in vitro antimalarial activity of isoxanthochymol (6) against Plasmodium falciparum shows strong chemosuppression of parasitic growth.
Asunto(s)
Antimaláricos/aislamiento & purificación , Garcinia/química , Plasmodium falciparum/efectos de los fármacos , Triterpenos/aislamiento & purificación , Xantonas/aislamiento & purificación , Animales , Antimaláricos/química , Antimaláricos/farmacología , Cristalografía por Rayos X , Malaria Falciparum/parasitología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Rotación Óptica , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Plasmodium falciparum/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Triterpenos/química , Triterpenos/farmacología , Xantonas/química , Xantonas/farmacologíaRESUMEN
A new diterpenoid, limbetazulone (= (3S,4S,4aR,12bS)-1,2,3,4,4a,5,6,11,12,12b-decahydro-3-hydroxy-4-(hydroxymethyl)naphtho[1',2': 5,6]cyclohepta[1,2-b]furan-7(7H)-one; 1), with the very rare 'naphtho[2,1-f]azulene-7-one' skeleton, was isolated from the aerial parts of the Asian medicinal plant Ballota limbeta. Its structure was established by extensive spectroscopic investigations, especially 1D and 2D NMR. X-Ray diffraction studies showed the presence of two conformational isomers (1a and 1b) in the crystal.