Cytotoxicity of a new tirucallane derivative isolated from K. Schum stem bark.

One new tirucallan derivative, leutcharic acid () was isolated from stem bark together with the known compounds 3-oxo-22-hydroxyhopane (), 3,4-secotirucalla-4(28),7,24-trien-3,21-dioic acid (), 3-oxotirucalla-7,24-dien-21-oic acid (), lupeol (), -sitosterol () and stigmasterol (). The structures of the isolated compounds were elucidated using 1 D and 2 D NMR spectroscopy in combination with literature data. To the best of our knowledge, this is the first report on the cytotoxic properties' constituents of . Cytotoxicity of compounds and was assessed with the WST-1 assay on human lung adenocarcinoma A549 and THP-1 human monocytic leukaemia cell lines. Both compounds showed antiproliferative activity on the cancer cells. Compound was more active against THP-1 with an IC value of 26.83 µM. The sensitivity of THP-1 cells to compounds and indicated that these compounds might be potential leads for anticancer agent development against leukaemia.