Macrocyclic [N5] transition metal complexes: synthesis, characterization and biological activities

Novel penta-azamacrocyclic 21-membered [N5] ligand [L] and its transition metal complexes with Co(II), Ni(II), Cu(II), Ru(III) and Pd(II) have been isolated and characterized. The mode of bonding and overall geometry of the complexes have been inferred through IR, MS, UV–Vis, EPR, 1H NMR spectral studies, molar conductivity, magnetic, thermal and microanalyses, On the basis of above studies, an octahedral geometry has been proposed for all complexes except Pd(II) chloride complex which adopt square planar geometry. The in vitro antitumor activity of the synthesized ligand and some selected complexes against human breast and human hepatocarcinoma cell lines (MCF-7) and (HePG2), respectively has been studied. The results show that the tested compounds are potent antitumor agents. Also the ligand and some selected complexes have been tested for their inhibitory effect on the growth of bacteria: Streptococcus pyogenes as Gram-positive bacteria and Escherichia coli as Gram-negative bacteria. The activity data show that most of the tested compounds exhibit remarkable antibacterial activity against these organisms.