Biological evaluation of transition metal complexes of benzothiazole Schiff base as potential antimicrobial and anticancer agents

In this present work, we have investigated the biological activities of4-chlorophenyl)-1-(2-hydroxyphenyl)prop-2-en-1-one(chalcone)and benzothiazole appended Schiff base ligand and its metal(II) complexes. Density functional theory (DFT) calculations were done to infer the electronic properties of the ligand, providing insights into its coordination behavior and potential bioactivity; similarly metal(II) complexes show electronic structure. Antioxidant activity of prepared compounds shows that, prepared complexes have better efficiency than Schiff base ligand. Moreover, bovine serum albumin interactions of ligand and its Co(II), Ni(II) and Cu(II) complexes were analyzed by spectrophotometric and fluorometric methods. The results have suggested that, the prepared ligand and its compounds can interact with BSA molecule via static quenching method. Moreover, calculated binding constant (Kapp), quenching constant (Ksv), rate constant (Kass) values of Ni(II) complex (Kapp, 6.2 × 104 M−1; Ksv, 3.099 × 103; Kq, 3.099 × 1011 and Kass, 4.368 × 104) is higher than other complexes and ligand. In vitro cytotoxicity studies against HeLa cancer cells using the MTT assay showed that all metal(II) complexes possessed remarkable anticancer potency than the ligand, with the Ni(II) complex exhibiting the lowest IC50 value, signifying the highest cytotoxic effect. These findings highlight the promising antioxidant, protein-binding, and anticancer properties of the synthesized metal(II) complexes, supporting their potential therapeutic applications.