Synthesis, characterization and theoretical calculations of some Mn(II), Zn(II) and Cd(II) macrocyclic Schiff base complexes containing 2-hydroxy-5-methylisophthaldehyde

Two new branched hexadentate amines, 4,7- bis (2-pyridylmethyl)-4,7-diazaundecane-1,10-diamine (L5) and 5,8-bis(2-pyridylmethyl)-5,8-diazadodecane-1,12-diamine (L6), have been synthesized. Condensation with 2-hydroxy-5-methylisophthalaldehyde in the presence of manganese(II), zinc(II) and cadmium(II) ions in methanol leads to produce six new Schiff base macrocyclic complexes [MSb1]2+ and [MSb2]2+ with two 2-pyridylmethyl pendant arms. The resulting compounds were characterized by IR, elemental analysis, Mass and by 1H and 13C NMR in the case of Cd(II) and Zn(II). These compounds are quite stable in air and can be stored in a desiccator for long periods without decomposition. The synthesized complexes were screened for their antibacterial activities against four bacterial; (Escherichia coli) PTcc 10009,) Bacillus cereus (ATCC 7064,) taphylococcus subrogation (Lio) و Staphylococeus aureus (ATCC 6633, strains and the complexes showed antibacterial effects.