RESUMO
Four new stilbene derivatives, polygonumosides A-D (1-4), were isolated from the processed roots of Polygonum multiflorum. Their structures were elucidated by spectroscopic analysis, including 1D and 2D NMR and ECD. Polygonumosides A (1) and B (2), possessing an unprecedented tetracyclic skeleton, were assigned as 2S- and 2R-2-(4-hydroxyphenyl)-9,10,11-trihydroxy-2H-benzo[c]furo[2,3-f]chromen-7(3H)-one-4-O-ß-d-glucopyranosides, respectively, while polygonumosides C (3) and D (4) were assigned as a pair of diastereomeric stilbene glucoside dimers.
Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Glucosídeos/isolamento & purificação , Polygonum/química , Estilbenos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Glucosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Estilbenos/químicaRESUMO
Two new phenylpropanoid glycosides, 1,3,4-tri-O-(E)-caffeoyl-ß-d-glucopyranoside (1) and 1,4-di-O-(E)-caffeoyl-ß-d-glucopyranoside (2), along with four known phenylpropanoid glycosides (3-6), were isolated from the roots of Aruncus sylvester. The structures of 1 and 2 were elucidated using various spectroscopic methods. Compounds 1 and 2 displayed significant scavenging activity of 2,2-diphenyl-1-picrylhydrazyl free radicals with IC50 values of 110 and 258 µM (ascorbic acid: IC50 = 574 µM).