Anti-Salmonellal Schiff Bases from Vanillin: Synthesis and Structure Elucidation

A series of vanillin substituted Schiff bases namely; 2-methoxy-4-(pyridine-3-yl-hydrazonomethyl)-phenol, NT1 (1), (4-hydroxy-3-methoxybenzylidene) isonicotinohydrazide, NT2 (2), 4-[(2,4-dinitrophenyl) hydrazonomethyl]-2-methoxyphenol, NT3 (3), 2-methoxy-4-phenyliminomethyl-phenol, NT4 (4) were synthesized using vanillin and four aromatic amines: nicotinic acid hydrazide, 2,4-dinitrophenylhydrazine, isoniazid and aniline and their anti-salmonellal activity examined and reported in this work for the first time. The synthesized compounds were characterized by Nuclear Magnetic Resonance (NMR), Fourier Transformer-Infrared (FT-IR) and melting points. The anti-salmonellal activity of the synthesized compounds was studied in comparison with their reactants (amines and vanillin) using the disc diffusion and micro dilution method using 14 isolates of Salmonella typhi. The activity of compounds was consistent in both assays. The compounds showed overall relatively low in vitro bacteriostatic activity.