The mixed-ligand copper(II) complex (2,2'-bipyridine)[1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(piperazin-4-ium-1-yl)quinoline-3-carboxyl­ato]nitratocopper(II) nitrate dihydrate

The drug norfloxacin and ligand 2,2'-bipyridine coordinate to copper(II) yielding a mixed-ligand complex, [Cu(C₁₆H₁₈FN₃O₃)(NO₃)(C₁₀H₈N₂)](NO₃)·2H₂O or [Cu(H-Norf)(NO₃)(bpy)](NO₃)·2H₂O. The Cu^II atom has a five-coordinate environment with square-based pyramidal geometry, which involves two N atoms from the 2,2'-bipyridine ligand, two O atoms from the norfloxacinate ligand and one nitrate O atom. Weak interactions between O and Cu result in a centrosymmetric dimer.