Metal based pharmacologically active agents: Synthesis, structural elucidation, DNA interaction, in vitro antimicrobial and in vitro cytotoxic screening of copper(II) and zinc(II) complexes derived from amino acid based pyrazolone derivatives

The paper presents the synthesis of complex combinations of Cu(II) and Zn(II) with Schiff base obtained by the condensation reaction of 4-aminoantipyrine with benzaldehyde and 2-amino-3-methyl-butanoicacid. Structural features of synthesized compounds were determined by analytical and spectral techniques. Binding of synthesized complexes with calf thymus DNA (CT DNA) was studied by spectroscopic methods and viscosity measurements. Experimental results indicated the ability of the complexes to form adducts with DNA and to distort the double helix by changing the base stacking. Oxidative DNA cleavage activities of the complexes were studied with supercoiled (SC) pUC19 DNA using gel electrophoresis. The in vitro antimicrobial screening effects of the investigated compounds were monitored by the disk diffusion method. The synthesized Schiff base complexes exhibited higher antimicrobial activity than the respective free Schiff base. The in vitro cytotoxicity of synthesized complexes against Ehrlich ascites carcinoma (EAC) tumor model was investigated using trypan blue dye exclusion assay. The complexes possessed significant cytotoxic activity.