Structural, Spectroscopic, Quantum Chemical and Molecular Docking Studies on 2-Aminopyridinium Dihydrogen Phosphate: A Potential Multi-Target Bioactive Molecule
Pyridine-based compounds constitute an important class of molecules with broad pharmaceutical relevance owing to their diverse biological activities. Among these, 2-aminopyridine is widely used as a versatile precursor for the construction of heterocyclic frameworks. This work describes the growth of a proton-transfer single crystal, 2-aminopyridinium dihydrogen phosphate (2APDHP), using the slow solvent evaporation technique. Single-crystal X-ray diffraction confirmed that the crystal belongs to the monoclinic system. Structural optimization was carried out at the HF and DFT levels with the 6-311++G(d,p) basis set, providing detailed information on the molecular geometry, bond distances and bond angles. The electronic characteristics were examined through frontier molecular orbital calculations. Experimental FT-IR and Raman spectra were interpreted with the aid of theoretical vibrational calculations, yielding close agreement between the calculated and observed frequencies. Molecular docking was performed to examine the interaction of 2APDHP with α-synuclein of Parkinson’s disease, 6-hydroxymethyl-7,8 dihydropteroate synthase from Mycobacterium tuberculosis and the SARS-CoV-2 main protease.