Antioxidative Phenolics from the Fresh Leaves of <i>Ternstroemia japonica</i>

Abstract

Six new phenylethanoid glucosides, ternstrosides A-F (1-6), a new kaempferol derivative (7), and eight known compounds were isolated from the fresh leaves of Ternstroemia japonica. The structures were elucidated by 1D and 2D NMR spectroscopic analyses. Compounds 1-7 showed potent antioxidative activity in three different tests, with IC50 values in the range 3.26-6.50 microM in the hydroxyl radical (*OH) inhibitory activity test, 33.29-82.21 microM in the total ROS (reactive oxygen species) inhibitory activity test, and 1.14-13.53 microM in the peroxynitrite (ONOO-) scavenging activity test.