Three new xanthones, named kaennacowanols A–C (1–3), along with nineteen known
xanthones were isolated from the roots of Garcinia cowa Roxb. Their structures were
determined by spectroscopic analysis. All isolated compounds were evaluated for their
cytotoxicity against KB and HeLa cell lines. Compounds 17 and 22 showed good cytotoxicity
against KB cell with IC50 values of 7.97 and 9.10 μM, respectively. On the other hand,
compound 15 showed good cytotoxicity against HeLa cell with IC50 value of 9.34 μM.