Synthesis, Characterization, Thermodynamics Studies and Antibacterial Activity of Same Mononuclear Complexes with Ligand Derived from 4-Aminoantipyrine with Threonine Amino Acid

Abstract

The heterocyclic ligand potassium 2-(((Z)-1,5-dimethyl-4-((E-1-(4-nitrophenyl) ethylidene) amino)-2-phenyl-1,2-dihydro-3H-pyrazol-3-ylidene) amino)-3-hydroxybutanoate (K₄-AP-NO₂A-Thr) has been synthesized under the thermal condition from the combination of 4-aminoantipyrine, 4-nitroacetophenone, and Threonine. A new series of transition metal complexes of Mn(II), Co (II), Ni(II),Cu(II) and Zn (II) has been produced from the Schiff base(K₄-AP-NO₂A-Thr). The geometry structures of the ligand and the complexes were determined through FT-IR, UV-Vis, ¹H-NMR spectroscopy, (C.H.N) analysis, as well as molar conductance and magnetic susceptibility. These studies revealed that tetrahedral structure was suggested for Co (II) and Cu (II) complexes. Yet, the octahedral structure was suggested for Mn(II), Ni (II) and Zn (II) complexes. In-vitro antibacterial activity of the synthesized ligand and its complexes against (S. aureus, K. aureus) was evaluated through the disc diffusion method. Thermodynamic values were studied by conductivity methods. The conductivity of solution complexes prepared at different temperatures in aqueous water was measured using the Lee-Wheaton equation to obtain the values of ionic molar conductivity (?), the association constant (K_A), distance parameter (R), and (?_º).