Synthesis and Antibacterial Activity of Erythromycin 9-Acylhydrazone Derivates.

Background: Some species of Marine bacteria pose great risks to human and mariculture organisms. Meanwhile, Vibrio harveyi and Vibrio parahaemolyticus strains have acquired resistance to many antibiotics.

Objective: A novel series of erythromycin 9-acylhydrazone derivatives were synthesized and evaluated for their in vitro antibacterial activity against marine pathogens.

Methods: The site-selective N-acylation of erythromycin hydrazone was achieved using acid chloride/ triethylamine in methanol as the reaction system. All the synthesized target compounds were evaluated for their antibacterial activity by determination of minimum inhibitory concentrations (MICs) using the broth microdilution method.

Results: All the tested acylhydrazone compounds showed moderate to high activity with MIC value 0.125-1 μg/mL against Vibrio parahaemolyticus and Vibrio harveyi.

Conclusion: The introduction of the acylhydrazone moiety at the C-9 position of erythromycin improved its activity against the above-mentioned marine bacteria strains.