Synthesis and Characterisation of Transition Metal Complexes Derived from 4-Aminoantipyrine and Thiosemicarbazide Based Schiff Base

Abstract

Abstract A novel Schiff base ligand was synthesized through the condensation of 4-Aminoantipyrine with 1, 3-isophthaldehyde and Thiosemicarbazide. The Schiff base ligand and its metal complexes of Co(II), Ni(II), Cu(II) and Zn(II) were synthesized and characterized by elemental analyses, molar conductance, magnetic susceptibility measurement , IR, UV-Vis, 1 H NMR, Mass and EPR spectral studies. The data showed that the complexes have composition of [ML]Cl 2 stoichiometry. The conductivity data confirmed the electrolytic nature of the complexes. The metal complexes of Co (II), Ni (II), and Zn (II) were showed an octahedral configuration. The electronic absorption spectra of the Cu (II) complex suggested a square- planar geometry around the central metal ion further it was confirmed by the EPR spectrum. The IR spectral data suggest the involvement of sulphur and azomethine nitrogen in coordination to the central metal ion. The interaction of the complexes with calf thymus (CT) DNA has been studied using absorption spectra and Cyclic Voltammetric measurement. The metal complexes exhibit effective cleavage of pBR 322 DNA from the super coiled form to the open circular form. The synthesized complexes have been subjected to antimicrobial study. The antimicrobial results indicated that the antimicrobial activity of the complexes show the enhanced activity in comparison to free ligand. These findings are giving suitable support for developing new anti cancer and antimicrobial agent and expand our scope for applications.