Fractionation of a methanolic extract of the leaves of Anthurium versicolor has resulted in the isolation of two main fractions, I and II. Both the extract and the fractions were assayed for their radical-scavenging activity by means of an in vitro test (bleaching of the stable 1,1-diphenyl-2-picrylhydrazyl radical) and showed a significant radical-scavenging effect. Subsequent chromatographic fractionation of the most active fraction, II, has led to the isolation and characterization, as major constituents, of four new flavone glycosides, acacetin 6-C-[alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranoside] (1), acacetin 6-C-[beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside] (2), acacetin 6-C-[beta-D-apiofuranosyl-(1-->3)-beta-D-glucopyranoside] (3), and acacetin 8-C-[alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranoside] (4), as well as vitexin (apigenin-8-C-beta-D-glucopyranoside) and rosmarinic acid. The structures of 1-4 were determined using spectroscopic methods.

No abstract

Analysis of a methanolic extract of Tagetes lucida leaves has resulted in the isolation of a new flavonol glycoside, quercetagenin 3,4'-dimethyl ether 7-O-beta-D-glucopyranoside (1), two new phenolic acids, 3-(2-O-beta-D-glucopyranosyl-4-methoxyphenyl)propanoic acid (2) and its methylester (3), and known flavonols, aromatic acids, and 7-methoxycoumarin. Using the DPPH degrees test, the extract and some of its constituents showed a significant free-radical-scavenging effect in comparison to alpha-tocopherol and standard flavonols.