Chemical quantitative and spectroscopic study of a new derivative of dapsone drug and some of its new complexes Zn(II), Cd(II) and Hg(II) as antibacterial agents

In this study, we synthesized newly derived ligands and sulfonamides by preparing azo dyes containing the (N=N) group and subsequently linking them to the Schiff base (CH=N) group. This process formed compounds that combine both functional groups, resulting in heterocyclic organic compounds known as azo-azomethine compounds. which are unique in their applications as antibiotics, as well as transitional element bonds, where this article included the study of the theoretically created ligands based on the theory (DFT) using the Gaussian program after determining its structure practically by spectroscopic methods (1H-NMR., FT-IR.). The calculated values ​​of the HOMO and LUMO parameters and the calculated quantitative properties indicate the stability of the synthesized ligand and were tested on gram-positive bacteria (S. aureus) as an application of its antimicrobial properties. The derivative ligand showed an effect only at high concentrations. In contrast, the mercury complex showed the highest effect at each concentration, followed by the cadmium complex at high concentrations due to the toxicity of these metals. The zinc complex's different concentrations did not show any significant inhibition of bacteria that could be considered. KEY WORDS: Dapsone drug, DFT, Metal Complexes, Azo-azomethine, Antimicrobial Bull. Chem. Soc. Ethiop. 2025, 39(9), 1723-1732. DOI: https://dx.doi.org/10.4314/bcse.v39i9.6