Synthesis, Characterization and Biological Studies on 3d-Metal Complexes of 5-[(1, 5-Dimethyl-3-oxo-2-Phenyl-2, 3-Dihydro-1H-Pyrazol-4-yl) Diazenyl]-1-Ethyl-6-Hydroxy-4-Methyl-2-oxo-1, 2-Dihydropyridine-3-Carbonitrile

N-hetorocyclic ligand 5-[(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) diazenyl]-1-ethyl-6-hydroxy-4-methyl-2-oxo-1,2 Dihydro pyridine-3-carbonitrile (L) and a few of  their transition metal complexes have been synthesised  and  characterized by different physico-chemical techniques. The electronic and magnetic susceptibility measurements suggest an octahedral geometry for all the complexes excepting Zn(II) complex which possess tetrahedral geometry. The results of thermo-gravimetric analysis showed that the synthesized complexes have thermal stability and confirms the absence of coordinated or lattice water molecules. The bio-potency of all these compounds was investigated by using antimicrobial, antimycobacterial and cytotoxic activities. All the transition metal complexes were noticeably exhibited inhibition properties against the tested microbes.