New Triterpene Saponins from Duranta repens Linn. and Their Cytotoxic Activity

From the leaves of Duranta repens (Verbenaceae) two new triterpene saponins, named durantanin IV (1) and V (2) were isolated. In addition, ten known compounds were isolated, namely a bidesmosidic saponin, oleanolic acid, three phenylethanoids and five flavonoids. All metabolites were isolated for the first time from this genus except for 3 (oleanolic acid) and 7 (E/Z acteoside). The structures were determined mainly by spectroscopic methods (UV, IR, HRESI-MS, H-1-, C-13-NMR, H-1-H-1 COSY, HSQC and HMBC). Cytotoxic screening of the chloroform, ethyl acetate and methanol extracts was carried out on brine shrimps. In addition, the investigated methanol extract and compounds 1, 2 and 7 showed significant cytotoxic activity against a HepG2 cell line.