Rubochingosides A - J, labdane-type diterpene glycosides from leaves of Rubus chingii.

Ten previously undescribed labdane-type triterpenoids, rubochingosides A - J (1-10), were isolated from the leaves of Rubus chingii Hu. Their structures were elucidated by spectroscopic and chemical methods. The cytotoxicity of all isolated compounds was tested against five human tumor cell lines (Bel-7402, Caski, BGC-823, A2780, and HCT-116). Among them, compounds 4 and 8 showed cytotoxic activities against Bel-7402 and A2780 cells with IC50 values of 10.43 ± 0.51 and 29.03 ± 2.94 µM, respectively; Compound 8 exhibited cytotoxic activities against Bel-7402 and HCT-116 cells with IC50 values of 17.78 ± 1.54 and 26.23 ± 6.14 µM, respectively.