We report the synthesis of some novel azo Schiff bases based on benzothiazoles via a multi-stage synthetic approach. Synthesis of the target compounds included an intermediate, followed by an azo coupling reaction and a subsequent condensation reaction with different aromatic aldehydes. The chemical structures of the synthesized compounds were formally confirmed using spectroscopic techniques, including Fourier Transform Infrared Spectroscopy (FT-IR), Proton Nuclear Magnetic Resonance (¹H-NMR), and Carbon-13 Nuclear Magnetic Resonance (¹³C-NMR). Furthermore, the antibacterial activity was evaluated using the agar diffusion method against selected Gram-positive and Gram-negative bacterial strains. As a result, several derivatives displayed significant antibacterial activity. The above data strongly indicate that azo Schiff base compounds derived from benzothiazoles will represent a new group of potentially valuable antibacterial agents for further research. D4 and D1 were the most potent derivatives, indicating that both electron-donating and electron-withdrawing groups on the aromatic ring strongly affect antibacterial activity. In conclusion, the results show that benzothiazole azo dye Schiff base derivatives offer molecular scaffolds for new antibacterial drug development. More studies are requested to determine their mode of action and to fully assess their biological potential.
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