Phenol constituents of Pachysandra terminalis and their antioxidant activity

To study the phenol constituents from Pachysandra terminalis and their antioxidant activities.Constituent isolation and purification was carried by repeated column chromatography (silica gel, Toyopearl HW-40 and preparative HPLC), and their structures were elucidated on the basis of spectral data analysis. DPPH method was used to evaluate the free radical scavenging activity of the isolated compounds.Nine phenol compounds (1-9) were isolated and their structures were identified as follow: p-hydroxybenzaldehyde (1), vanillin (2), 1-(4-hydroxy-3-methoxyphenyl) -ethanone (3), syringaldehyde (4), salicylic acid (5), p-hydroxybenzoic acid (6), ferulic acid (7), 2,3,4-trihydroxybenzoic acid (8), 3,4-dihydroxybenzoic acid (9). The isolated compounds showed obviously antioxidant activity. At the concentration of 50 micromol x L(-1), compounds 7-9 revealed DPPH free radical scavenging rates were 87.8%, 97.8% and 92%, respectively.Compounds 1-9 were isolated from this genus for the first time. They showed the significant antioxidant activity.