Four chalcone glycosides (1-4), including three new natural products, and three flavanones (5-7) were isolated from the methanol extract of stem bark of Maclura tinctoria. The new compounds have been characterized as 4'-O-beta-D-(2"-p-coumaroyl)glucopyranosyl-4,2',3'-trihydroxychalcone (1), 4'-O-beta-D-(2"-pcoumaroyl-6"-acetyl)glucopyranosyl-4,2',3'-trihydroxychalcone (2), and 3'-(3-methyl-2-butenyl)-4'-O-beta-D-glucopyranosyl-4,2'-dihydroxychalcone (3); the known derivatives were elucidated as 4'-O-beta-D-(2"-acetyl6"-cinnamoyl)glucopyranosyl-4,2',3'-trihydroxychalcone (4), eriodictyol 7-O-beta-D-glucopyranoside (5), naringenin (6), and naringenin 4'-O-D-beta-glucopyranoside (7). Their structures were determined by 1D and 2D NMR and ESIMS. The antioxidant activity of all the isolated compounds was determined by measuring free-radical-scavenging effects using two different assays, namely, the Trolox Equivalent Antioxidant Capacity (TEAC) assay and the coupled oxidation of beta-carotene and linoleic acid (autoxidation assay). The results showed that compound 3 was the most active in both antioxidant assays.
|Autori interni:||BRACA, ALESSANDRA|
|Autori:||G. CIOFFI; L. MORALES ESCOBAR; A. BRACA; N. DE TOMMASI|
|Titolo:||Antioxidant chalcone glycosides and flavanones from Maclura (Chlorophora) tinctoria|
|Anno del prodotto:||2003|
|Digital Object Identifier (DOI):||10.1021/np030127c|
|Appare nelle tipologie:||1.1 Articolo in rivista|