Synthesis, spectral characterization, DFT studies, and computational screening of 4-amino-3-mercapto-5-methyl-1,2,4-triazole and its cadmium(II) mixed ligands complexes as potential antimalaria drug

Abstract

In this research paper we report the detailed synthesis, spectral (¹H-NMR, FT-IR, and UV-Vis), crystal structure determination, DFT studies, and molecular modeling of 4-amino-3-mercapto-5-methyl-1,2,4-triazole (L₂) Schiff base ligand and its complexes of cadmium as suitable bioactive agents for the treatment of malaria. From the spectroscopic results, the synthesized schiff base has potentialtridentate coordination with themetal ion via hydroxy naphthalinic-O, azomethine-N and sulphur atom of the thione group. First principle theoretical calculations within the framework of density functional theory (DFT) were conducted to scrutinize the stability, reactivity, energetics, and the nature of bonding interactions in the studied schiff base and its complexes. In-silico molecular simulation was also executed to comprehend the conformation of interaction of the studied compounds against malaria (ILS5) protein for possible treatment of the disease. The observed binding affinity for the ligand (L₂), its mono-ligand complex [CdL₂Cl], mixed ligands complex [CdL₂TH] Cl and the standard drug are -7.23, -7.63, -7.3, and -7.60 kcal/mol, respectively, indicating that the Schiff base and is Cd²⁺ complexes have the potential to be developed into therapeutic drug for the treatment of malaria.