α-Amino nitrile complexes of Cr, Co, Ni, AND Cu: Synthesis, characterization, and biological evaluation

Abstract

Many studies have been conducted in the field of α-amino nitrile complexes. A new series of metal ion complexes for Cr(III), Co(II), Ni(II), and Cu(II) was derived from the α-aminonitrile 2-(2-hydroxyphenyl)-2-(o-tolylamino)acetonitrile ligand (HL). The complexes have been characterized using conventional techniques such as (FT-IR), (UV-VIS) spectroscopy, (C.H.N.M), metal chlorides, thermal analysis, ¹H-NMR, molar conductivity and magnetic moment. Octahedral geometries were suggested for the new complexes, while the Ni-complex was suggested as a pseudo-tetrahedral geometry, according to the magnetic moment value (3.11 B.M.) and the electronic spectrum; they were observed to be electrolytic. The coordination behavior of the ligand was bidentate, of the NO-type, through hydroxyl and amine groups. Antibacterial activity has been evaluated for the synthesized compounds against Pseudomonas, Escherichia coli, Proteus, and Staphylococcus aureus; the results were promising, considering the presence of a free nitrile moiety and metal ions, which influenced the structure-activity relationship. Antioxidant activity was observed using the DPPH assay, where the ligand and complexes exhibited radical scavenging activity IC₅₀% in the range of (0.012-0.005) compared to gallic acid. Anticancer activity studies revealed that the Cu(II) complex showed the highest cytotoxicity with the lowest IC₅₀ value (224.67 µM), indicating enhanced activity upon complexation.

KEY WORDS: α-Aminonitrile, Bi-dentate ligand, Anti-bacterial activity, Electrolytic

Bull. Chem. Soc. Ethiop. 2026, 40(10), 2173-2183.                             

DOI: https://dx.doi.org/10.4314/bcse.v40i10.9