Synthesis, spectroscopic characterization and anti-microbial activities of (z)-4-(4-(dimethylamino)benzylideneamino)-1, 5-dimethyl-2-phenyl-1h-pyrazol-3(2h)-one schiff base ligand and its divalent metal complexes

Abstract

Five Schiff base complexes derived from Ni(II), Zn(II), Cu(II), Co(II) and Fe(II) salts were prepared and investigated using FTIR, ¹³CNMR, ¹HNMR, GCMS, and UV/Visible electronic spectra. The Schiff base was derived from a reaction between 4-aminoantipyrine and 4-(N,N-dimethylamino)benzaldehyde. The ligand formed was complexed with different metals salts to study their chemical and microbial behaviours. From the results, the Infra-red data revealed the proper coordination sites of the ligand to the metal ions and displayed the different groups in the compounds. The UV/Visible electronic spectra data showed the different transfers and transitions in the ligand and metal complexes. The different absorptions in the electronic spectra also predicted the possible structures of the complexes. The ¹³CNMR and ¹HNMR showed the different carbon and hydrogen environments in the ligand and complexes. The GCMS confirmed the structure of the ligand and exhibited different fragments. The antimicrobial activities of the ligand were enhanced with the metal complexes and the results were very interesting as the complexes showed good antifungal and antibacterial activities.

Key Words: 4-aminoantipyrine, antibacterial, antifungal, complexes, Schiff base