New water soluble bis-imidazolium salts with a saldach scaffold: Synthesis, characterization and in vitro cytotoxicity/bactericidal studies

A series of water-soluble bis-imidazolium salts of the type H2(iPr)2saldach(1,2-Me2Im+-X−)2 (4) and their mononuclear complexes [M(III)Cl{(iPr)2saldach(1,2-Me2Im+-X−)2}] (M = Mn, 5; Fe, 6), (X = Cl, a; PF6, b; BF4, c), where saldach = N,N′-bis(salicylidene)-(±)-trans-1,2-diaminocyclohexane, have been synthesized and characterized using elemental analysis, electronic, spectral, magnetic as well as conductometric methods and MALDI-TOF-, ESI-MS. All complexes possess a distorted square pyramidal coordination geometry with MN2O2Cl chromophore, as revealed by the elemental, spectral and literature data. These salts have been evaluated for in vitro cytotoxicity against HepG-2 and MCF-7 cell lines. Among them, 4c (IC50 = 22.17 μM) exhibited potency against MCF-7. The bactericidal efficacy of 4a–c was screened against a panel of common pathogenic bacteria. Compound 4a was found to be the most potent antibacterial agent and could inhibit all the bacterial strains more effectively than standard antibiotics.