Iridoid glucosides from the leaves of Vitex negundo var. cannabifolia

Abstract Five new iridoid glucosides, cannabifolisides A–E (1 – 5), together with nine analogues (6 – 14), were isolated from the leaves of Vitex negundo var. cannabifolia. Their structures were elucidated by spectroscopic data (NMR, UV, IR, and MS) analyses and comparison of their spectroscopic and physical data with the literature values. The protective effect of isolated compounds on human gastric epithelial cells were evaluated by measuring the enhanced cell viability of GES-1 cell insulted by TCA. Among these, compounds 4, 6, 8, 10, 12, and 14 remarkably increased the cell viability in a concentration-depend manner.