Triterpenoids and sterols from the grains of Echinochloa utilis Ohwi & Yabuno and their cytotoxic activity.

Two new tetracyclic triterpenoids, echinochlorins C (1) and D (2), and sawamilletin (3) with new spectroscopic data were isolated from Echinochloa utilis Ohwi & Yabuno grains, along with one known triterpenoid (4) and eight sterols (5-12). Their structures were elucidated by spectroscopic data analyses (IR, UV, MS, and NMR). These compounds were tested in vitro cytotoxic activities against the human tumor-cell lines (HeLa, HL-60, and MCF-7). Compounds 6 and 8 displayed potential cytotoxic activity against HeLa, with IC50 values of 3.1±0.9 and 3.2±0.8μM, respectively. This finding indicated that tetracyclic triterpenoids isolated from E. utilis may have potential beneficial effects for the treatment of cancer.