Use of the Fusion Method to Preparation and Bioactivity Evaluation of Novel Benzo-Oxazepine Derivatives

Abstract

In this study, Schiff base and phthalic anhydride were reacted using the melting technique without the use of solvents to produce a series of oxazepine-4,7-dione (SH20–SH25). The success of the chemical procedure was confirmed by spectroscopic methods (UV-Vis, IR, 1H-NMR, 13C-NMR) that confirmed the structure of the produced compounds and revealed the distinctive patterns of carbonyl groups, aromatic bonds, and oxazepine. Additionally, the biological effectiveness of SH22 and SH24 against two pathogenic bacterial species—Escherichia coli (Gram-negative) and Escherichia coli (Gram-positive)—was tested as part of the study, using three different concentrations, and comparing them to the standard antibiotics ciprofloxacin and amikacin. SH22 showed moderate activity against E. coli at its highest concentration (2.1 cm), while it showed weak activity against Staphylococcus aureus. In contrast, SH24 showed significant activity against both strains at high concentrations, outperforming standard antibiotics. These results show the potential of new oxazepine compounds as antibacterial agents, especially SH24. Further studies should be conducted to evaluate the possible mechanisms of action and potential future uses of these compounds.