Dinuclear Copper(II) and Molybdenum(VI) Complexes of Bis-Tridentate Hydrazonylthiophene: Synthesis and Biochemical...

An economical multidentate 2,5-dicarbohydrazide-(2-hydroxybenzylidene)thiophene ligand (HL) was synthesized in a facile way. For the coordination capability, HL bonded to Cu²⁺ and cis-MoO₂ ²⁺ cations for the design of two new complexes of CuL and cis-MoO₂L, respectively. The inhibitive action of HL (as a free organic reagent) impacted by its complexing forms in CuL and cis-MoO₂L on the proliferating capacity of various microorganism series and normal/tumor cell lines of humankind was examined, and their antioxidant capacity was evaluated. Consequently, Cu²⁺ and cis-MoO₂ ²⁺ cations exhibited modified biochemical actions against the developed proliferation of the bacterial-fungal and tumor cells over the uncoordinated HL ligand through the measured areas of microorganisms' dead zones (mm) and the half-maximal inhibitory concentrations (IC₅₀, µM) of the proliferated tumor cell lines in vitro, spectroscopically. The affinity of binding strength and modes of HL, CuL, and cis-MoO₂L with calf thymus DNA (ctDNA) were estimated by the variations in the viscometric and colorimetric characteristics of the current compounds, referring to the obvious effect of Cu²⁺ and cis-MoO₂ ²⁺ cations with their high electronegativity and redox potential. Spectroscopic analyses were employed to examine the interaction of HL, CuL, and cis-MoO₂L with ctDNA through the derived data of K_b and $\Delta G_b^{\ne }$ , as 1.31, 1.55, and 1.61 × 10⁶ mol^{- 1} dm³, and as -40.14, -44.38, and -45.43 kJ mol^{- 1}, respectively. Hence, Cu²⁺ and cis-MoO₂ ²⁺ cations demonstrated a significant influence on the biological action of their complexes based on their different charges, oxidation states, and coordination geometries relative to the uncoordinated organic HL ligand.