Template Synthesis of Macrocyclic Complexes of Co(II), Ni(II) and Cu(II) Metal Ions: Spectroscopic and Biological Evaluation.

Macrocyclic complexes with bivalent metal ions Co(II), Ni(II), Cu(II) have been synthesized by [2+2] condensation of 2,6 pyridine di carboxylic acid and thiourea by template method in ethanolic medium. The synthesized complexes have been characterized with the help of various physico-chemical techniques viz. elemental analyses, magnetic susceptibility, conductivity measurements and spectral (IR, UV and EPR) techniques. The low value of molar conductivity indicates the non-electrolyte nature of the complexes. All the complexes are of high-spin type. On the basis of above studies an octahedral geometry has been assigned for Co(II) and Ni(II) complexes whereas tetragonal geometry around the Cu(II) ion. The biological activities of the metal complexes have been tested in vitro against a number of bacterial species to assess their inhibiting potential. Cu(II) complexes were found to more active as compared to Co(II) and Ni(II) complexes. [ABSTRACT FROM AUTHOR]