A New Taraxastane Triterpene from Euphorbia Denticulata with Cytotoxic Activity Against Prostate Cancer Cells

In this research, aerial parts of Euphorbia denticulata Lam were collected from Sanandaj city in Kurdistan province at the West of Iran. It was extracted by maceration using acetone as solvent. The isolation of compounds were carried out with repeated column chromatography using silica gel and normal preparative HPLC using YMC-Pack-Sil column and hexane: ethyl acetate as mobile phase. The structures of isolated compounds were elucidated by extensive 1 and 2D-NMR as well as HRESI-MS spectra and the cytotoxicity was done against DU-145 human prostate cancer cell line using standard MTT assay. It afforded a new 12-taraxastane derivative and two known cycloartane triterpenes including: taraxast-12-ene-3 beta, 20,21(alpha)-triol (1), cycloartane-3 beta, 25-diol (2), and cycloartane-3 beta, 24,25-triol (3). They exhibited cytotoxic effects, with IC50 values of 12.2 +/- 2.9, 27.5 +/- 4.9, and 18.3 +/- 1.4 mu M, respectively.