SYNTHESIS, SPECTRAL ELUCIDATION, ANTIBACTERIAL, ANTIOXIDANT AND DNA STUDIES OF ONNO TETRADENTATE SCHIFF BASE METAL(II) COMPLEXES DERIVED FROM 2-AMINOPHENOL DERIVATIVES

The new asymmetrical tetradentate (ONNO) Schiff base (L) 4-chloro- 2- ((E)- (4- ((E)-((2-hydroxy-5-nitrophenyl)imino)methyl)benzylidene) amino)phenol was prepared by the condensation of terephthalaldehyde with 2-amino 4-chlorophenol and 2-amino 4-nitrophenol in 1:1:1 molar ratio in methanol. The homo binuclear metal(II) complexes were synthesized in ligand to metal ratio 2:2 from the template method. The composition, geometry and binding sites of ligand and its complexes were determined by various studies like Elemental, molar conductance, electronic, magnetic moment, FT-IR, ¹H and ¹³C-NMR, ESI-Mass, EPR, Thermal, and PXRD. The above spectral studies show that the Schiff is a dibasic tetradentate (ONNO), and its metal complexes possess a square planar structure. The biological applications of all compounds were tested for antibacterial, antioxidant, and DNA cleavage, and the final reports reveal high inhibition activity for metal(II) complexes compared to the ligand. The DNA binding activities of Cu(II) complex was observed by electronic absorption method. Antitumor activity of Cu(II) complex was screened for their cancer-inhibiting ability against MCF-7 human breast cancer cells by using the MTT experiment.