The reactions of Cu(II) with the mixed nitrilotriacetic acid (H(3)NTA) and 4,4'-bipyridyl (4,4'-bpy) ligands in different metal-to-ligand ratios in the presence of NaOH and NaClO4 afforded two complexes, Na-3[Cu-2(NTA)(2)(4,4'-bpy)]-ClO(4)center dot 5H(2)O (1) and [Cu-2(NTA) (4,4'-bpy)(2)]ClO(4)center dot 4H(2)O (2). The two complexes have been characterized by elemental analysis, IR, XRD, and single-crystal X-ray diffraction. 1 contains a basic doubly negatively charged [Cu-2(NTA)(2)-(4,4'-bpy)](2-) dinuclear unit which was further assembled via multiple Na-O and O-(HO)-O-... interactions into a three-dimensional (3D) pillared-layer structure. 2 features a two-dimensional (2D) undulated brick-wall architecture containing a basic doubly positively charged [Cu-4(NTA)(2)(4,4'-bpy)(2)](2+) tetranuclear unit. The 2D network possesses large cavities hosting guest molecules and was further assembled via O-(HO)-O-... hydrogen bonds into a 3D structure with several channels running in different directions.