A new ONNO-type azomethine ligand, 2,2′-(ethane-1,2- diylidenedinitrilo)dibenzoic acid, (YLH<inf>2</inf>) (1) has been prepared by the condensation of 2-aminobenzoic acid and glyoxal. The coordination compounds [Ni(YL)] (2), [Co(YL)] (3), [Cu(YL)(H<inf>2</inf>O)] (4), [Zn(YL)] (5), and [Cd(YL)] (6) of the YLH<inf>2</inf> ligand with five transition metal ions, Ni(II) Co(II), Cu(II), Zn(II), and Cd(II) have been prepared. The structures of these new azomethine compounds are proposed on the basis of the elemental analyses, proton nuclear magnetic resonance, infrared, ultraviolet-visible spectroscopy, and X-ray powder diffraction patterns. Elemental analyses indicate a ligand metal ratio of 1:1 in the coordination compounds. X-ray powder diffraction parameters for [Cu(YL)(H<inf>2</inf>O)] and [Cd(YL)] compounds correspond to orthorhombic and monoclinic structures, respectively. The ligand acts as a tetradentate ligand bending through oxygen atoms of the hydroxyl groups of benzoic acid and nitrogen atoms of the azomethine groups. In addition, the ligand and its metal complexes have been studied for their possible genotoxic potential. © 2011 Wiley Periodicals, Inc.