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(Reference retrieved automatically from SciELO through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

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

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Author(s):
Carmem L. Cardoso ; Dulce H. S. Silva ; Ian Castro-Gamboa ; Vanderlan da S. Bolzani
Total Authors: 4
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