Cytotoxic activity of sesquiterpene lactones from Inula britannica on human cancer cell lines

Five new sesquiterpene lactones (1-5) were isolated from Inula britannica collected in the wild from Serbia along with five known compounds (6-10). Sesquiterpene lactones were isolated using centrifugal partition chromatography followed by combination of flash chromatography and semi-preparative HPLC. Isolated compounds were screened for cytotoxic activity on four different human cancer cell lines and their multi-drug resistant counterparts, as well as on normal human keratinocytes. Sesquiterpene lactones showed similar cytotoxic activity toward drug sensitive and drug resistant cancer cell lines. (C) 2013 Phytochemical Society of Europe. Published by Elsevier B. V. All rights reserved.