Biological activity and biomolecule interaction of pyridyl thiazole derivative and its copper complex

Abstract

This article discusses the synthesis of pyridyl thiazole derivative (PT) and its copper complex (PTC − Pyridyl Thiazole Copper Complex) for studies related to biological activities and biomolecule interaction. Synthesized compounds were characterized, and their biological activities were tested. The metal complex, PTC exhibited positive antibacterial and anticancer activity. The complex PTC inhibited MCF-7 cells at IC50 of 516 µg/mL as compared to the ligand PT which showed IC50 of 868 µg/mL. The PT ligand showed inhibition of S. aureus with a minimum inhibitory concentration (MIC) of 50 µg/mL. While PTC exhibited inhibition against both S. aureus and E. coli organisms with MIC of 50 µg/mL and 150 µg/mL respectively. The binding interaction of two important biomolecules such as Human Serum Albumin (HSA) and Deoxyribonucleic acid (DNA) with both free ligand and metal complex were studied to determine the type and nature of reaction and forces involved in the process. The Ksv values obtained from fluorescence experiments to determine the interaction of PT/PTC with HSA illustrated a static quenching mechanism. Circular dichroism analysis showed minor changes in α-helix percentage, suggesting a lesser influence of these compounds on the secondary structure of HSA. Molecular docking demonstrated a binding pose for PTC with ΔG = −7.51 kcal/mol, supporting the experimental findings in this study. PTC showed more strong interaction with DNA compared to the ligand. Results obtained depict that the PTC complex may have the potential to be used in cancer treatments and antibacterial applications.