SYNTHESIS, CHARACTERISATION, THERMAL ANALYSIS AND DNA CLEAVAGE ACTIVITY OF A NOVELZINC (II) COMPLEX OF PYRAZOLE SCHIFF BASES

Abstract

A hydrazone Schiff base Zn(II) metal complex is synthesised from the Shiff base ligand Thiophene-2-carboxylic acid hydrazide and 1, 3-diphenyl-1H-pyrazole-4-carboxaldehyde reacted together in 1:1 mole ratio to obtain Schiff base ligand (HL) which was subsequently, allowed to react with Zn(CH3COO)2.2H2O. The Schiff base ligand and its Zn (II) complex prepared were characterized on the basis of elemental nalysis,thermogravimetry, UV-Visible spectroscopy, FT-IR spectroscopy and NMR spectroscopy. IR spectrum of the zinc complex shows that the ligand (HL) is coordinated to the metal ion in monoanionicbidentate fashion with the 1:2 metal to ligand stoichiometry. The thermal behaviour of thecomplex shows a single step decomposition pattern leaving the respective ZnO residue. The DNA cleavage activity of the complex ismonitored using agarose gel lectrophoresis method which indicates the potential of the complex to cleave supercoiled DNA.