Two new iridoid glycosides from the root barks of Sambucus williamsii Hance.

Chemical investigation of the ethanol extract of the root barks of Sambucus williamsii Hance collected in the Heilongjiang province of China resulted in the isolation of two new iridoid glycosides, williamsoside A (1) and williamsoside B (2). Their structures were elucidated on the basis of extensive spectroscopic analysis (1D, 2D-NMR and HRESIMS) and chemical studies. Iridoid glycosides have for a long time been considered as characteristic ingredients of S. williamsii. However, the presence of iridoid glycosides with apiofuranosyl moieties in S. williamsii is reported for the first time in this study.