Protection of phenylpropanoid glycosides from Pedicularis against oxidative hemolysis in vitro.

Five phenylpropanoid glycosides from Pedicularis, isoacteoside (1), acteoside (2), echinacoside (3), pedicularioside A (4), cistanoside D (5), and a chemically synthesised compound, permethylacteoside (6), as phenolic compounds can protect against oxidative hemolysis. The inhibitory activity is related to the number of phenolic hydroxy groups. Compounds 1, 2, 3, and 4, possessing four phenolic hydroxy groups, have stronger inhibitory activities than 5 possessing only two phenolic hydroxy groups, and compound 6 with no phenolic hydroxy group inhibited oxidative hemolysis weakly.