Mononuclear and tetranuclear alkali metal complexes: Synthesis, structural characterization, and in vitro anti-cancer and antimicrobial studies

Abstract

In this report, we present five new alkali metal complexes (1– 5) that displayed excellent anticancer and antibacterial activities in solutions. 1,10-phenanthroline (phen), salicylic acid (sa) benzoic acid (ba), and p-aminobenzoic acid (paba) ligands were employed in complexation reactions. The complexes were characterized by a variety of analytical techniques including infrared and UV–vis spectroscopy, elemental analysis, 1H NMR, 13C NMR, and single-crystal X-ray diffraction analysis. We described the structures of three mononuclear lithium complexes [Li(phen)2(sal)] (1), [Li(phen)2(ba)] (2), {[Li(phen)(H2O)3].(paba)} (3), a mononuclear sodium complex [Na(phen)(paba)(H2O)] (4) and an unsual tetranuclear cesium complex [Cs4(phen)4(paba)4(H2O)2] (5). The complexes in solution displayed excellent activities against oral and lung cancer cells with the least toxicity toward normal cells when compared to the standard drug 5-fluorouracil and cisplatin.