Cyclofarnesane sesquiterpene glucoside from the whole plant of Loranthus tanakae and its cytotoxicity

The whole plants of Loranthus tanakae were repeatedly extracted with 80% aqueous MeOH and the concentrate was partitioned into ethyl acetate (EtOAc), n-butyl alcohol (n-BuOH) and H2O fractions. The repeated silica gel (SiO2), octadecyl SiO2 (ODS), and Sephadex LH-20 column chromatographies for the n- BuOH fraction led to isolation of a cyclofarnesane sesquiterpene glucoside. The chemical structure including stereo structure was determined to be a (1‘R,3‘S,5‘R,8‘S,2E,4E)-dihydrophaseic acid 3'- O-Β-D-glucopyranoside on the basis of spectroscopic analyses. This compound was isolated for the first time from L. tanakae in this study. Compound 1 showed a moderate dose-dependent cytotoxicity against human Caucasian gastric adenocarcinoma cells and human hepatocyte cari-noma cells cell lines at higher than 50 µg/mL.