In this study, a new tetraimine Schiff base (T1) was obtained by the synthesis of diimine Schiff base (D1), the reduction of nitro group of this Schiff base to amino group and the reacting of amino group with 2-hydroxy-1-naphthaldehyde, respectively. It was characterized by various spectroscopic techniques. The phenol-keto tautomerism of Schiff base (T1) was investigated by UV–vis spectra in different solvents and media. The binding interaction between T1 and metal ions, i.e., Cr3+, Fe3+, Ni2+, Zn2+, Cu2+, Co2+, Pb2+, Ag+ and Ba2+ was confirmed in DMF-HEPES buffer (v/v, 1:1) by UV–vis spectroscopy. It showed the favorable coordination toward Cu2+, Co2+ and Fe3+ ions. In the presence of Cu2+, Co2+ and Fe3+ ions, yellow color of T1 solution changed to colorless. The 1:1 binding stoichiometry between T1 and Cu2+, Co2+, Fe3+ ions was established using Job’s plot. The binding constants (Ka) were calculated to be 1.22 x 104 M-1, 1.62 x 104 M-1 and 5.79 x 104 M-1 for Cu2+, Co2+ and Fe3+ ions, respectively, by Benesi–Hildebrand equation. In addition, T1 was also found to be potent scavenger of DPPH radicals with half-maximal scavenging concentration (SC50) value less high than that of the standard, ascorbic acid.