Objective: The objective of this search is to design, and synthesize new mutual prodrugs in order to obtain synergistic antibacterial activity. Methods: The hydroxyl group of three antioxidants (menthol, thymol, and vanillin), was linked to chloroacetyl chloride through nucleophilic substitution reaction, to give intermediates (Ia-Ic), which were reacted with a carboxyl group of Gatifloxacin to form three final compounds (I-III) having ester linkage. Results: The Antibacterial activity effect of the target compounds (I-III) has been tested for in vitro inhibitory activity against Gram-positive bacteria: Staphylococcus aureus and Gram-negative bacteria: Escherichia coli by using spots diffusion method. All the tested compounds show a remarkable antibacterial activity against tested bacteria. Conclusion: The synthesized prodrugs were characterized and identified through FT-IR spectroscopy, 1H-NMR spectrum, and various physicochemical parameters. The antibacterial study of the compounds showed various activities toward the two types of pathogenic bacteria which are Staphylococcus aureus and Escherichia coli. Compounds [I, II, and III] revealed that Staphylococcus aureus was sensitive to synthesized compounds but Escherichia coli showed a reverse activity with some resistance for antibacterial drugs.
