Biologically relevant macrocyclic complexes of copper spectral, magnetic, thermal and antibacterial approach

Copper(II) macrocyclic complexes have been synthesized with five novel ligands: L-1-1,7,10,16-tetraaza-2,6,11,15-tetraone-4,13-dithiacycloocta-decane, L-2-1,7,11,17-tetraaza-2,6,12,16-tetraone-4,14-dithia-cyclocosane, L-3-1,7,10, 13,19,22-hexaaza-2,6,14,18-tetraone-4,16-dithiacyclo-tetracosane, L-4-1,7,14,20,tetraaza-2,6,15,19-tetraone-4,17,di- thiatricyclo [22, 4, O-21,O-26, O-8,O-13] hexacosa-8,10,12,21,23,25-hexene, L-5- 1,7,13,19,25,26-hexaaza-2,6,14,18 tetraone-4,16 dithia tricyclo [23, 3, 1, I-8,I-12] hexacosa [8(26), 10, 12, 20(25), 22, 24] hexane and characterized by elemental analysis, molar conductance, magnetic susceptibility, i.r, u.v.-vis, EPR spectral studies, thermal studies and electrochemical properties. The molar conductance measurements of the complexes in DMSO correspond to 1:2 electrolytes. g-Values are calculated for all of the complexes in the polycrystalline form as well as in DMSO solution. On the basis of i.r, electronic and EPR spectral studies a square planar geometry has been assigned to these complexes. Cyclic voltammograms for all the complexes are similar to quasi-reversible redox processes (CuCuII)-Cu-II reversible arrow (CuCuI)-Cu-II reversible arrow Cu-I Cu-I. The complexes were also evaluated against the growth of bacteria (S. fecalis and E.coli) in vitro