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

In this study, we have outlined a conventional and user-friendly procedure for the production of (E)-1-(((5-ethyl-1,3,4-thiadiazol-2-yl)imino)methyl)naphthalen-2-ol (HL-1) and (E)-1-((thiazol-2-ylimino)methyl)-naphthalen-2-ol (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 1H 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-Co (II), HL-1Cu (II), complexes and ligands HL-2Co (II), and HL-1Ni(II) had positive effects on Escherichia coli causing severe stomach cramps (Gram-negative- MTCC 1610) and positive impact on Staphylococcus aureus (Gram-positive MTCC-96) due to skin infections.