Crystal Structure, Quantum Chemical, Hirshfeld Surface and Molecular Docking of Organic Molecular Salt: 2-Amino-5-Chloropyridinium-2,4-Dihydroxybenzoate

An organic molecular salt, 2-amino-5-chloropyridinium-2,4-dihydroxybenzoate (ACP-DHB) is synthesized by the slurry method followed by crystallization from methanol. The formation of molecular salt is initially confirmed by 1H and 13C nuclear magnetic resonance (NMR) spectral data. Single crystal X-ray diffraction (XRD) analysis shows that the crystal belongs to the monoclinic crystal system with space group, P21/n. Further, the supramolecular assembly involved the extensive network of N+-H center dot center dot center dot O- and N-H center dot center dot center dot O hydrogen bonds as well as C-Cl center dot center dot center dot O halogen bond. Using UV-Visible spectral data, the optical band gap is calculated and found to be 4.21 eV. Photoluminescence studies indicate the crystal has blue light emission properties. TG/DTA analysis shows that ACP-DHB is thermally stable up to 162 degrees C. The quantum chemical calculations and natural bond analysis (NBO) are performed at B3LYP/6-311G++ (d,p) basis set using Gaussian 09 software. The relative contributions of various intermolecular connections are discussed using Hirshfeld surface analysis and fingerprint plot illustration. The antibacterial and antifungal activity exhibits better inhibitory capacity against pathogens. Molecular docking revealed that ACP-DHB efficiently binds with the 1UAG and 5KEE targets and has strong binding ability to the proteins. ADMET factors and Lipinski's rule of five are used to predict drug likeness property. The 2-amino-5-chloropyridinium-2,4-dihydroxybenzoate crystal is developed and described through single-crystal XRD and DFT calculations. The packing in the crystal is examined through Hirshfeld surface analysis. The antimicrobial potential of ACP-DHB crystal is verified by the disc diffusion method and molecular docking.image