Reducing Activity of Polyphenols with Stable Radicals of the TTM Series. Electron Transfer versus H-Abstraction Reactions in Flavan-3-ols
- 29 October 2004
- journal article
- Published by American Chemical Society (ACS) in Organic Letters
- Vol. 6 (24), 4583-4586
- https://doi.org/10.1021/ol048015f
Abstract
A new method to test the antioxidant activity of polyphenols by electron transfer reactions to a stable organic free radical, tris(2,4,6-trichloro-3,5-dinitrophenyl)methyl radical (HNTTM), is reported. Therefore, the activity of the natural flavanols, (−)-epicatechin, and two synthetic derivatives, 4β-(S-cysteinyl)epicatechin and 4β-(2-aminoethylthio)epicatechin, can be differentiated by their capacity to transfer hydrogen atoms to 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and to transfer electrons to HNTTM.Keywords
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