A new hybrid ligand and its metal complexes from a natural plant (Styrax officinalis) bearing egonol, thiosemicarbazone and oxime units, and their anti-cancer activities

A novel hybrid ligand, a vic-dioxime ligand (ETO), containing thiosemicarbazone and egonol moieties from a natural plant (Styrax officinalis) and its trinuclear [Ni(II), Cu(II), Co(II), and Fe(II)] and mononuclear [Pd(II) and Zn(II)] complexes have been synthesized and characterized. The ligand, complexes, and natural components were characterized by conventional spectroscopic techniques (IR, NMR, and MS) and evaluated against two human cancer cell lines (MCF-7 and PC-3) to determine their antiproliferative and apoptotic properties. Apoptotic or necrotic effects were detected in both cancer cell lines using the Hoechst/propidium iodide double-staining method. Paclitaxel was used as a positive control (1 mu M). The results displayed that the compounds obtained in this study were effective in the concentration range of 5-40 mu M in prostate and breast cancer cell lines. It can be said that the compounds (egonol, its derivatives, hybrid ligand, and its metal complexes) are mostly more effective in PC-3 migration lines. Consequently, the cytotoxic efficiencies of [Cu-3(ETO)(2)center dot 4Cl], 5.27 mu M for MCF-7 and 13.44 mu M for PC-3 and [Zn (ETO)center dot 2Cl] 11.73 mu M for MCF-7 and 9.32 mu M for PC-3 were observed to be close to paclitaxel (a drug used as a cancer chemotherapeutic agent). [Cu-3(ETO)(2)center dot 4Cl] were more effective on the MCF-7 cell line. Besides this result, [Zn (ETO)center dot 2Cl] was more effective on the PC-3 cell lines and was more effective by triggering apoptosis in the cells.