Physicochemical characterization and anticancer activity of the new imipramine based Co(II), Pd(II) and Mn(II) compounds

Three new imipramine-based compounds, namely: (HIMP)2CoCl4, (HIMP)2Pd2Cl6 and (HIMP)2MnCl4 (HIMP = protonated imipramine) were synthesized in a single-step reaction between imipramine hydrochloride and metal (II) chlorides. The physicochemical properties of all three compounds were thoroughly investigated using appropriate analytical techniques: single crystal and powder X-Ray diffraction analysis, elemental analysis, UV-Vis and FTIR spectroscopies, fluorescence measurements, quantum mechanical calculations, TG-DTG thermogravimetric analysis and magnetic studies. The investigations proved the high purity of the compounds and the isostructurality of (HIMP)2CoCl4 and (HIMP)2MnCl4 compounds. Of all compounds, only (HIMP)2MnCl4 exhibited fluorescent properties. When heated, all three compounds decompose, yielding the appropriate metal (II) oxides in the case of (HIMP)2CoCl4 and (HIMP)2MnCl4 compounds or metallic palladium in the case of (HIMP)2Pd2Cl6. In the last step, the anticancer activity of all three compounds was evaluated against MKN-74, PANC-1, SCOV-3, MDA-MB-231, MDA-MB-468, A-375 and SK-MEL-28 cell lines. Cytotoxicity evaluation revealed that the incorporation of the active metal ions significantly increased the imipramine activity against all tested cancer cell lines without significant toxicity against normal fibroblasts.