New biflavonoid and other flavonoids from the leaves of Chimarrhis turbinata and their antioxidant activities

Author(s)

Carmem L. Cardoso ; Dulce H. S. Silva ; Ian Castro-Gamboa ; Vanderlan da S. Bolzani

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 16, n. 6b, p. 1353-1359, Nov.- Dec. 2005.
• Field of knowledge: Physical Sciences and Mathematics - Chemistry

Abstract

A new biflavonol, named chimarrhoside (1), and eight known flavonol glycosides (2-9), were isolated from the leaves of Chimarrhis turbinata. Their structures were established on the basis of 1D and 2D NMR experiments as quercetin-3-O-rutinoside (2), kaempferol-3-O-rutinoside (3), kaempferol-3-O-alpha-L-rhamnopyranosyl-(1->6)- beta-D-galactopyranoside (4), quercetin-3-O-alpha-L-rhamnopyranosyl-(1->6)- beta-D-galactopyranoside (5), 6-hydroxy-rutin (6), kaempferol-3-O-D-galactopyranoside (7), kaempferol-3-O-D-glucopyranoside (8) and kaempferol-3-O-alpha-L-rhamnopyranosyl-(1->6)- alpha-L-rhamnopyranosyl-(1->4)-beta-D-glucopyranoside (9). In addition, catechin (10) and catechin-(4<FONT FACE=Symbol>a®</FONT>8)-catechin-procyanidin B-3) (11) were isolated. The crude extract, fractions and isolated compounds were evaluated for their antioxidative properties using an autographic assay based on beta-carotene bleaching on TLC plates, and spectrophotometric detection by reduction of the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. Flavonoids 2, 5, 6, 10 and 11 displayed strong free radical scavenging activity, when compared with the standards BHT and rutin. (AU)

• FAPESP's process: 03/02176-7 - Conservation and sustainable use of the diversity from Cerrado and Atlantic Forest: chemical diversity and prospecting for potential drugs - phase II
• Grantee: Vanderlan da Silva Bolzani
• Support type: BIOTA-FAPESP Program - Thematic Grants