The mixed-ligand complexes are prepared by the reaction of thiobarbituric acid with five-coordinate Co(II), Ni(II) and Cu(II) of arylideneanthranilie acids. The so obtained complexes are characterised by elemental analyses, electronic and IR spectroscopy, X-ray powder diffraction patterns, and conductivity measurements. It is found that thiobarbituric acid coordinates as a neutral or mono-basic mono-dentate ligand to form carboxylate-bridged five-coordinate mixed-ligand complexes. Both the ligands and mixed-ligand complexes have been tested for their antimicrobial activities.