Exploring the multifaceted potential of pyridine-2,6-dicarboxylic acid–methyl carbazate compounds: Crystallographic analysis, biological activity, theoretical insights, and environmental catalysis

Abstract

Novel salts of pyridine-2,6-dicarboxylic acid (PD) with methyl carbazate (MCZ) in 1:1, 1:2, and 2:1 molar ratios—denoted as PM1, PM2, and PM3, respectively—were synthesized in a methanol–water solvent mixture. These salts were characterized through elemental analysis, FTIR, UV–vis, ¹H NMR, mass spectrometry, and TG–DTA. PM1, crystallized in the P2₁/c space group, was further analyzed using single-crystal X-ray diffraction, which revealed considerable O–H (24.8 %) and H–H (24.2 %) interactions, as identified through Hirshfeld surface analysis. Density functional theory calculations indicated narrow HOMO–LUMO energy gaps and favorable electronic properties. In silico absorption, distribution, metabolism, excretion, and toxicity analysis suggests that these salts may possess drug-like properties. Molecular docking studies supported strong binding affinities, particularly for PM1, with bacterial proteins from Staphylococcus aureus (PDB ID: 3KOR) and Escherichia coli (PDB ID: 5WEZ). Among the three salts, PM1 demonstrated the most potent antibacterial activity against these pathogens, correlating with its highest antioxidant capacity in DPPH radical scavenging assays. The antibacterial results were consistent with the docking data, confirming PM1 as the most effective antibacterial agent. The catalytic potential of these salts was further investigated by evaluating their ability to reduce toxic nitrophenol compounds, specifically o-nitrophenol and p-nitrophenol. PM1 exhibited the highest catalytic efficiency in these reduction reactions, indicating its potential for environmental detoxification. Owing to its outstanding biological and catalytic performance, PM1 is a promising candidate for both pharmaceutical and environmental applications.