Perpustakaan Digital ITB

The potential of the first series transition metal complexes with Schiff's base ligand as an antioxidant is widely studied by researchers. In this study, hydrazone-type Schiff base compounds, salicylaldehyde-2,4-dinitrophenylhydrazone (SDPH), resulted from condensation of salicylaldehyde (1.5 mmol) and 2,4- dinitrophenylhydrazine (1.5 mmol) has been synthesized. The structure of SDPH has been characterized by 1H-NMR. The synthesized SDPH are used as ligands in formation of its Cu(II) and Co(II) metal complexes. The Cu(II)-SDPH and Co(II)- SDPH complexes were synthesized from metal ion and ligand with reflux reaction at 60 oC for 6 hours in molar ratio 1:2 and 1:3, respectively. Triethylamine is used to synthesis Co(II)-SDPH, which serves to deprotonate SDPH ligands. Dimeric and neutral charge of complexes are obtained by ESI-MS analysis. The resulting Cu(II)- SDPH and Co(II)-SDPH complexes have the chemical formula [Cu2(SDPH)2(H2O)4(OH)2] ([M+Na]+ = 858 g/ mol) and [Co2(SDPH)2[(Et)3N]2(acn)2(OH)2} ([M+Na]+ = 1061 g/ mol), shown on the ESIMS spectrum. Coordinate bonds between Cu (II) or Co (II) metal ions with ligands are observed in the presence of shifting of the C= N wave number, as well as the loss of the vibrating peaks of the O-H groups to the infrared spectra of each complexes. The IR spectrum of complexes was suggested that SDPH behave as a bidentate ligand through the azomethine nitrogen atom and phenolic oxygen atom. The Cu(II) and Co(II) complexes were paramagnetic in nature. The ligand and its Cu(II) and Co(II) complexes have been screened for antioxidant activity against DPPH (2,2-diphenyl-1-picrylhydrazine). Based on the results of the activity test, IC50 values of Cu(II)-SDPH and Co(II)-SPDH complexes were lower than those of the SDPH ligands. These results show that the two complexes of SDPH are potentials as antioxidants.