Two new 5(14)-membered type cyclopeptide alkaloids from root bark of Ziziphus spina-christi (L.) Desf.

Six 5(14)-membered ring type of cyclopeptide alkaloids (CPAs), including two undescribed members, 1-hydro,2β-methoxy-mauritine-A ( 1 ) and 1-hydro,2α-methoxy-mauritine-A ( 2 ), together with four known compounds, mauritine-A ( 3 ), mauritine C ( 4 ), amphibine-A ( 5 ), and amphibine-E ( 6 ), were isolated from the root bark of Ziziphus spina-christi (L.) Desf., Their structures were determined by multiple spectral analyses, including UV, IR, 1D NMR, 2D NMR, EI-MS, HR-EI-MS, FAB-MS and ESI-MS, and by comparison with literature. All six CPAs were tested in vitro for cytotoxicity by three human cancer cell lines (MCF7, H460 and Hela) and a human normal cell line (BJ). None of the compounds showed cytotoxicity towards all tested cell lines.