Evaluation of Aminoacetophenoneoxime derivatives of oxime Schiff bases as a new antimicrobial agent.

ABSTRACT

Schiff bases may be a core to synthesize different new chemical ligands. They also have many biological activities by its azomethine group. Antimicrobial activities of new synthetic oxime derivatives against bacteria and fungi were investigated. o-Aminoacetophenoneoxime (o-AAOX) and m- Aminoacetophenoneoxime (m-AAOX) were used as precursors in the synthesis of five oxime derived ligands (L1-5). Two tridentates (L1 and L4) were derived from o-AAOX and three bidentates (L2, L3, and L5) were derived from m-AAOX. The structure of prepared ligands was confirmed using FT-IR, NMR (1 H and 13 C), and UV-Visible spectral analysis as well as melting point and element analysis. Antimicrobial activities of five ligands were determined by the disk diffusion method. Only the m-AAOX ligands showed an antimicrobial action. The L2 was the most effective ligand on the tested microorganisms, especially against Staphylococcus aureus (MIC, 8 mg/ml) and Candida glabrata (MIC, 5.5 mg/ml). The L5 ligand showed only antifungal effect. Kocuria rosea was resistant to all ligands, while Candida albicans was susceptible to most of them. In conclusion; the m-AAOX derivatives are an active compound against bacteria and fungi than the o-AAOX derivatives. The ligand L2 has more inhibitory effects on bacteria, while fungi were inhibited by other m-AAOX derivatives. The new Schiff bases of the m-AAOX derivatives may be regarded as promising antimicrobial agents.