SYNTHESIS, CHARACTERIZATION, AND IN VITRO BIOLOGICAL INVESTIGATION OF A CYCLOHEXYL-PHENYL HYDRAZONE DERIVATIVE

Abstract

The increasing prevalence of antimicrobial resistance has intensified the search for novel bioactive compounds with improved therapeutic efficacy. In the present study, a new hydrazone-based Schiff base derivative, 2-((1E)-((cyclohexyl(phenyl)methylene)hydrazono)methyl)-6-methoxyphenol, was synthesized through the condensation reaction of (Z)-(cyclohexyl(phenyl)methylene)hydrazine with 2-hydroxy-3-methoxybenzaldehyde under reflux conditions. The synthesized compound was obtained as a yellowish solid with a yield of 76% and a melting point of 166 °C. Structural elucidation was carried out using FT-IR and ¹H NMR spectroscopic techniques. The FT-IR spectrum exhibited characteristic absorption bands corresponding to azomethine (C=N) functionalities at 1575 and 1618 cm⁻¹, while the ¹H NMR spectrum confirmed the presence of cyclohexyl, aromatic, methoxy, hydroxyl, and azomethine proton environments consistent with the proposed molecular structure. The antibacterial activity of the synthesized Schiff base was evaluated against Staphylococcus aureus and Escherichia coli using the agar well diffusion method. The compound demonstrated promising antibacterial activity, producing inhibition zones of 18 ± 0.5 mm against S. aureus and 14 ± 0.6 mm against E. coli. The observed activity is attributed to the synergistic influence of the azomethine, hydroxyl, methoxy, and aromatic moieties present in the molecule. The results indicate that the synthesized hydrazone-Schiff base possesses significant antibacterial potential and may serve as a valuable scaffold for the development of new antimicrobial agents. Further investigations involving minimum inhibitory concentration, minimum bactericidal concentration, and mechanistic studies are recommended to explore its full pharmacological potential.