Single crystal structure features, optimization of ultrasonic conditions, density functional theory studies, and antibacterial activity of a new organic compound

Abstract

The synthesis of a novel water-soluble organic compound, N’-acetyl-4-nitrobenzohydrazide, was successfully achieved using hydrothermal and sonochemical methods. The resulting products, denoted as 1 and 2, were obtained as single crystals and powder, respectively. Characterization of the crystals through single-crystal X-ray diffraction (SC-XRD) indicated a monoclinic system with space group -P 2yn. Elemental analysis (CHN), energy-dispersive X-ray spectrometer (EDS), Fourier transform infrared spectroscopy (FT-IR), thermal analysis (TGA/DTA), and powder X-ray diffraction pattern (PXRD), were utilized to analyze the molecular structure of 1 and 2, confirming their identical nature. Furthermore, scanning electron microscopy (SEM) was employed to examine the surface morphology of compounds 1 and 2, revealing distinct morphological features and varying particle dimensions. The impact of time, temperature, and ultrasonic energy was examined to optimize the morphology and particle size of compound 2. A density functional theory (DFT) study was performed to find the role of intramolecular hydrogen bond (IHB) interactions on the capability of the different tautomers of newly synthesized organic compounds. Various properties such as total energies of tautomers, energies of the most important molecular orbitals, electronegativity, thermodynamic functions, molecular electrostatic potential (MEP) maps, electron charge densities, and aromaticity were computed. The antimicrobial activity of 1, and 2 have been evaluated against one Gram-positive (Staphylococcus aureus, ATCC 25923) and one Gram-negative (Escherichia coli, ATCC 25922) using the disc diffusion method. The analysis of the inhibition zones revealed that 2 exhibit enhanced antibacterial efficacy compared to 1. This observation suggests that particle size reduction may contribute to increased antibacterial activity, potentially due to enhanced interaction with bacterial targets.