Synthesis, Characterization, and Study of Anti-Microbial Properties of Fe (III) Schiff Base Complex Derived from Hydrazone and Benzaldehyde

Abstract: In this study, a hydrazone Schiff base ligand and its Fe(III) complex were synthesized. The hydrazone ligand was derived from hydrazone and benzaldehyde, and its antimicrobial properties were systematically evaluated. The synthesis of the Schiff base ligand was done by the condensation of 2-(2-aminothiazol-4-yl)acetohydrazide with 2-nitrobenzaldehyde, followed by complexation with FeCl₃ in a 1:2 molar ratio. Characterization was achieved using spectroscopic and analytical techniques, including ¹H-NMR, FTIR, UV-Vis, and XRD, which confirmed the successful formation of the ligand and its coordination to Fe(III). The ¹H-NMR spectrum confirmed the formation of the imine linkage (δ 8.09 ppm), while FTIR and UV-Vis data supported the presence of C=N bonding and metal-to-ligand charge transfer, respectively. XRD showed an amorphous structure consistent with flexible hydrazone linkages. Antimicrobial activity was screened against Escherichia coli, Salmonella typhi, Staphylococcus aureus, Streptococcus pyogenes, and Candida albicans using the agar well diffusion method. The Fe(III) complex demonstrated superior inhibitory activity compared to the free ligand, with the most significant enhancements observed against Staphylococcus aureus (20 mm vs. 16 mm) and Salmonella typhi (20 mm vs. 12 mm). These results suggest that metal coordination substantially enhances the antimicrobial efficacy of Schiff base ligands. The synthesized Fe(III) complex has potential as a lead candidate for the development of novel antimicrobial agents, given the rising issue of multidrug resistance.