Synthesis, X-ray structures, properties and SOD-like activity of ternary copper(II) complexes showing the N4O2 coordination with a combination of monodentate and bidentate N-donor ligands

► Five octahedral ternary Cu(II) complexes with the N4O2 coordination. ► One 1,10-phenanthroline, two adenine derivatives and two water molecules coordinate to the central Cu(II) atom. ► Four X-ray structures of [Cu(H2O)2(L1-4)2(phen)]·2MeOH (1-4). ► In vitro SOD-like activity with IC50 ≈ 104-146 μM.