Comparable catalytic and biological behavior of alternative polar dioxo-molybdenum (VI) Schiff base hydrazone chelates

Abstract

BackgroundAccording to the appreciable catalytic and biological reactivity of Mo-chelates with various based arylhydrazone organic framework, two dioxide-molybdenum (VI) chelates are produced with distinct polarity (MoL1, with high polar character and MoL2, with low polar feature). MethodsBoth Mo-pincer chelates are synthesized in equimolar ratios to their corresponded coordinated ligands (Schiff base hydrazone derivatives), resulting octahedral structures, which identified by alternative spectral techniques. The novelty here is the first attempt to study the catalytic action of both Mo-chelates in the brominative decarboxylation of α,β-cinnamic acid to the selective bromo-styrene product using hydrogen peroxide and potassium bromide at room temperature under homogeneous aerobic atmosphere (i.e. water). Comparable biological studies are based on the antimicrobial and anticancer assays, as well as, the ctDNA (calf thymus DNA) interaction, which investigated using various spectroscopic tools. The significant findingsAccording to the various polarity of the Mo-chelate catalysts, the high polar Mo-chelate (MoL1) has a better catalytic behavior for the yield of the selective product of 2-bromo-styrene derivative more than that of the less-polar Mo-chelate (MoL2), when water is used as the solvent. MoL1 and MoL2 optimize the catalytic system with 94 and 91% of the 2-bromo-product with 30 and 60 min, respectively. A mechanistic pathway is proposed to distinguish the role of Mo6+ ion for enhancing such catalytic processes spectroscopically. Based on the Tweedy's chelation theory, the effect of Mo6+ ion in their chelates is attributed by high antimicrobial and anticancer action, The interaction ctDNA is estimated with determination of the binding constants, Kb, and the negative values of Gibbs’ free energy, ΔGb≠, for both Mo-chelates depending on the spectroscopic shifts and changes.