Secoiridoid Glycosides from the Roots of Picrorhiza scrophulariiflora

A new secoiridoid glycoside, named picrogentioside D (1), has been isolated from the underground parts of Picrorhiza scrophulariiflora, together with three known compounds, picrogentioside C (2), scroneoside A (3), and scrophuloside B (4). Their structures were elucidated on the basis of spectroscopic evidence.