RESUMEN
A new derivative of epicatechin glucopyranoside, (2R,3R)-3,7,4'-trihydroxy-5,3'-dimethoxyflavan 7-O-ß-d-glucopyranoside (1), together with three mononuclear phenolic acid esters, methyl orsellinate (2), ethyl orsellinate (3) and methyl ß-orcinolcarboxylate (4) were isolated from the bark of Styrax suberifolius. The structures of 1-4 were determined on the basis of extensive analysis of NMR and MS spectra combined with chemical hydrolysis. The antifungal activities of the isolated compounds against three plant pathogenic fungi, Alternaria solani, Fusarium oxysporum and Phomopsis cytospore were evaluated using radial growth inhibition assay. Compounds 2, 3 and 4 exerted selective inhibitory activities against the tested fungi. Among of them, methyl ß-orcinolcarboxylate (4) exhibited obvious inhibitory effect against P. cytospore, with an inhibition rate of 86.72% at 100 µg/ml.
Asunto(s)
Antifúngicos/aislamiento & purificación , Catequina/aislamiento & purificación , Styrax/química , Alternaria/efectos de los fármacos , Antifúngicos/farmacología , Catequina/química , Catequina/farmacología , Hongos/efectos de los fármacos , Fusarium/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Extractos Vegetales/químicaRESUMEN
Five new cyclic diarylheptanoids (platycary A-E, compounds 1-5) and three previously identified analogues (i.e., phttyearynol (compound 6), myricatomentogenin (compound 7), and juglanin D (compound 8)) were isolated from the stem bark of Platycarya strobilacea. The structures of these compounds were determined using NMR, HRESIMS, and electronic circular dichroism (ECD) data. The cytotoxicity of compounds 1-5 and their ability to inhibit nitric oxide (NO) production, as well as protect against the corticosterone-induced apoptosis of Pheochromocytoma (PC12) cells, were evaluated in vitro using the appropriate bioassays. Compounds 1 and 2 significantly inhibited the corticosterone-induced apoptosis of PC12 cells at a concentration of 20 µΜ.
