4-Hydroxy-3-carboxycoumarin as an efficient building block for new ruthenium(II) complexes: synthesis, characterization, antibacterial, antioxidant and anti-inflammatory activities

A new 4-hydroxy-3-carboxycoumarin ligand and its ruthenium(II) complexes (1-5) have been synthesized, characterized and screened for their in vitro antibacterial activity against a range of Gram-positive and Gram-negative bacteria. In addition, compounds 1-5 were investigated for antioxidant activities using superoxide radical, 2,2-diphenyl-1-picrylhydrazyl radical and hydroxyl radical scavenging assays, in which most of them displayed significant antioxidant activities. Furthermore, compounds 1-5 were evaluated for anti-inflammatory activity using indirect haemolytic and lipoxygenase inhibition assays and revealed good activity. The new complexes were characterized using spectroscopic methods in addition to elemental analysis.