In-Situ Copper(II) Complexes of Some Quinolone Drug Ligands Were Discussed for Their Molecular Structures: Synthesis in Binary Solvent

Abstract

A series of copper solid complexes with different generation of quinolone drugs of the type [Cu(L)n(Cl)x(H2O)y]·zH2O ((1) L: nalidixic acid (Nal), n = 2, x = 2, y = 2, z = 9; (2) L: oxolonic acid (Oxo), n = 2, x = 2, y = 2, z = 2; (3) L: pipemidic acid (Pip), n = 2, x = 2, y = 2, z = 4; (4) L: lomefloxacin (Lom), n = 2, x = 2, y = 2, z = 2; (5) L: pefloxacin mesylate (Pef), n = 2, x = 2, y = 2, z 2; (6) L: levofloxacin (Lev), n = 2, x = 2, y = 2, z = 2) were synthesized and identified using micro-analytical, FT-IR spectroscopy, conductance data, effective magnetic moments, electronic UV-vis spectra, electron-spin-resonance (ESR) spectra. Except levofloxacin that behaves as bi-dentate fashion through oxygen atoms of pyridone and carboxylate groups, the other quinolone drug chelates acts as uni-dentate via nitrogen atom of pyridone/piperazyl moiety. Electronic spectroscopic tools are in agreement with an octahedral geometrical structure. Thermal degradation analyses TG-DTG in nitrogen gas environmental are discussed the number and location of water molecules. The thermal decomposition process is completely in 3–5 steps, that the first step is responsible to loss of uncoordinated water molecules. The stabilities of Cu(II) complex 1–5 were studied dependent on activations of energy E*, entropy ΔS*, enthalpy ΔH* and Gibbs free energy ΔG* that have been estimated using Coats-Redfern and Horowitz-Metzeger non-isothermal methods. Molecular docking was used to predict the binding between some quinolone drugs with the receptor of breast cancer mutant 3hb5-oxidoreductase.