A study of mononuclear 3d transition metal bis-Schiff base complexes: Synthesis, characterization, and evaluation of their antibacterial activity

Abstract

<p>In this study, we have outlined a conventional and user-friendly procedure for the production of <em>(E)-1-(((5-ethyl-1,3,4-thiadiazol-2-yl)imino)methyl)naphthalen-2-ol </em><em>(HL-1)</em> and <em>(E)-1-((thiazol-2-ylimino)methyl)-naphthalen-2-ol</em> (HL-2) by the reaction of heterocyclic amine, aldehyde in the presence of ethanol as a solvent and acid as the catalyst. The synthesis of new HL-1 and HL-2 may be accomplished with ease using this approach, which is also very efficient. In the presence of dipositive Co, Ni, and Cu metal complexation, HL-1 and HL-2 were carried out in the presence of metal: ligand (1:2). HL-1, HL-2, and metal complexes are characterized with the assistance of UV/visible, FT-IR, Mass, and <sup>1</sup>H NMR spectroscopy respectively. Furthermore, the ligands mentioned above (HL-1 and HL-2) and their metal complexes were tested for the antimicrobial study and showed an excellent inhibitory zone. These investigations indicated that HL1<strong>-</strong>Co (II), HL-1Cu (II), complexes and ligands HL-2Co (II), and HL-1Ni(II) had positive effects on <em>Escherichia coli</em> causing severe stomach cramps (Gram-negative- MTCC 1610) and positive impact on <em>Staphylococcus aureus</em> (Gram-positive MTCC<strong>-</strong>96) due to skin infections.</p>