Cytotoxic phenylpropanoid glycosides from Cirsium japonicum

Three new phenylpropanoid glycosides 1-3, along with nine known phenylpropanoid glycosides 4-12, were isolated from the aerial parts of Cirsium japonicum. The structures of isolated compounds were elucidated by chemical and spectroscopic methods. Compounds 1, 3, 6, 8, and 11 showed moderate cytotoxicities against MCF-7, U87, HCT116, and A549 cell lines with IC₅₀ values in the range of 1.35-11.32 μM. The known compounds 4-12 were obtained from this plant for the first time.