Two tridentate Schiff base ligands and their mononuclear cobalt (III) complexes: Synthesis, characterization, antibacterial and antifungal activities

Two Schiff base ligands (HL1, HL2) and their Co(III) complexes, [Co(HL1)(L1)] (1) and [Co(HL2)(L2)] (2) [where HL1 = 2-((E)-(2-hydroxyethylimino)methyl)-4-chlorophenol and HL2 = 2-((E)-(2-hydroxyethylimino)methyl)-4-bromophenol] were synthesized and characterized using spectroscopic methods. The crystal structures of 1 and 2 have been re-determined by single crystal diffraction at 100 K. The ligands and their Co(III) complexes were screened for antibacterial and antifungal activities by the disc diffusion, microdilution broth and single spore culture techniques. The antimicrobial activity of the Co(III) complexes and the free ligands exhibit antimicrobial properties and the Co(III) complexes show enhanced inhibitory activity compared with their parent ligand.

Graphical abstractTwo Schiff base ligands (H2L1, H2L2) and their Co(III) complexes, [Co(HL1)(L1)] (1) and [Co(HL2)(L2)] (2) [H2L1 = 2-((E)-(2-hydroxyethylimino)methyl)-4-chlorophenol and H2L2 = 2-((E)-(2-hydroxyethylimino)methyl)-4-bromophenol] were synthesized and characterized by spectroscopic methods. The schiff base ligands (H2L1 and H2L2) and the Co(III) complexes (1 and 2) were screened for the antibacterial and antifungal activities.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Two Schiff base ligands and Co(III) complexes. ► Antibacterial and antifungal activities were screened. ► Spectroscopic analysis. ► The crystal structure of 1 and 2 have been determined by single crystal diffraction at 100 K.