RESUMEN
An ethyl acetate extract the bark of Garcinia xanthochymus exhibited strong inhibition towards α-glucosidase and PTP1B with IC50 values of 0.3±0.1µg/mL and 2.3±0.4µg/mL, respectively. Chemical constituents of the extract were therefore examined, and two new compounds, xanthochymusxanthones A (1) and B (2), along with ten known xanthones (3-12), were isolated. Their structures were determined using spectroscopic methods, mainly 1D and 2D NMR. Inhibitory activity of the isolated compounds was then tested, and subelliptenone F (12) showed significant effect towards α-glucosidase with IC50 value of 4.1±0.3µM (compared with acarbose, IC50=900.0±3.0µM) whilst xanthochymusxanthone B (2) exhibited remarkable activity towards PTP1B with IC50 value of 8.0±0.6µM (compared with RK682, IC50=4.4±0.3µM).
Asunto(s)
Garcinia/química , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Xantonas/química , Xantonas/farmacología , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/metabolismo , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Hipoglucemiantes/farmacología , Modelos Moleculares , Corteza de la Planta/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Xantonas/aislamiento & purificación , alfa-Glucosidasas/metabolismoRESUMEN
Two new triterpenoids, entanolide (1) and methyl 3,4-secotirucalla-23-oxo-4(28),7,24-trien-21-al-3-oate (2), together with nine known compounds (3-11), were isolated from the bark of Entandrophragma angolense. Their structures were elucidated based on spectroscopic analyses, mainly 1 D and 2 D NMR spectral data. Compounds 1-6 and 8 were evaluated for their cytotoxicity against HepG2 cells, and compounds 2-5 exhibited weak activities.