A new phenylpropanoid glucoside from Psorospermum tenuifolium Kotschy (Hypericaceae)

A new phenylpropanoid glycoside named psorospermoside (1) possessing an allose unit was isolated from the Psorospermum tenuifolium Hook f. bark extract together with eleven known compounds. Their structures were elucidated using spectroscopic and spectrometric methods including 1D, 2D-NMR, and ESI-MS, as well as by comparison of their data with those reported in the literature. All the isolated compounds were assessed for their cytotoxicity effect on the human cervix carcinoma cell line KB3-1. Emodin (2) and its congener 2-geranylemodin (3) displayed significant cytotoxicity with IC50 values of 11.4 µM and 19.0µM, respectively. Furthermore, the chemotaxonomic significance of the isolated compounds was also discussed.