New Chemical Constituents from the Bark of Dendropanax morbifera Leveille and Their Evaluation of Antioxidant Activities

Four new constituents, as cis-6-oxogeran-4-enyl-10-oxy-O-beta-arabinopyranosyl-4 '-O-beta-arabinopyranosyl-2 ''-octadec-9',12',15'-trienoate (1), geran-3(10)-enyl-1-oxy-O-beta-arabinopyranosyl-4 '-O-beta-arabinopyranosyl-2 ''-octadec-9',12',15'-trienoate (2), geranilan-8-oxy-O-alpha-d-xylopyranosyl-2 '-n-octadec-9 '',12 '',15 ''-trienoate (3), 1-cyclohex-2 ', 5 '-dienyl 1-cyclohexylethanol-O-beta-d-xylopyranoside (4), along with six known constituents, guaiacol-O-beta-d-arabinopyaranoside (5), n-tetradecanyl oleate (6), oleyl-O-beta-d-xyloside (7), n-octadec-9,12-dienoyl-O-beta-d-arabinopyranoside (8), linolenyl-O-beta-d-arabinofuranoside (9) andglyceryl-1,3-dipalmito-2-olein (10), were isolated and identified from the Dendropanax morbifera bark. The new structures were established by one-and two-dimensional NMR (and in combination with IR, FAB-MSand HR-ESI-FTMS. The comparative evaluation of antioxidant potential by phosphomolybdenum, DPPH, FRAP and the NO assay of four different compounds (1-4), we have found that the compounds 1 and 2 have power as a natural antioxidant, whereas the compound 3 and 4 exhibited mild activity in comparison to compounds 1 and 2.