Synthesis, Spectral Characterization and Antimicrobial Activity of Schiff Base Ligands Derived from 4-Amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5- one

The Schiff bases of 4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one have attracted the attentionof the researchers because of their biological and analytical activities. These compoundsand its complexes provide a great variety of biological activity ranging from antitumor,fungicide, bactericide, anti-inflammatory, and antiviral activities [1-3]. In this research,we report the synthesis and crystal structures of Schiff base ligands derived from 4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one and substituted salicylaldehyde. These compoundsobtained through the condensation of substituted salicylaldehyde with 4-aminoantipyrine in ethanol at room temperature. These ligands were characterized by 1HNMR, 13C NMR, FT-IR and single crystal X-ray diffraction. The antibacterial activities of theSchiff base ligands were tested against the bacterial species Escherichia coli ATCC 25922(gram negativebacteria) and Staphylococcus aureusATCC 25923 (gram positive bacteria) bythe disc diffusion method. The experiments were performed in triplicates. The MIC of thechemically synthesized compounds was tested against bacterial strains through a broth dilutionsmethod.