title: μ-4,4'-Bipyridine-bis-[aqua-(4-hy-droxy-pyridine-2,6-dicarboxyl-ato)copper(II)].
abstract: The title compound, [Cu(2)(C(7)H(3)NO(5))(2)(C(10)H(8)N(2))(H(2)O)(2)], exhibits a centrosymmetric binuclear molecule. Each completely deprotonated 4-hy-droxy-pyridine-2,6-dicarb-oxy-lic acid mol-ecule assumes a tridentate chelating coordination mode. The square-pyramidal coordination geometry around the Cu(II) ion is completed by the bridging bipyridine ligand and an apical water molecule. Adjacent complexes are connected via O-H⋯O and C-H⋯O hydrogen bonds to generate a three-dimensional supra-molecular structure.
authors.affiliation: Shaanxi Key Laboratory of Chemical Reaction Engineering, Department of Chemistry and Chemical Engineering, Yan'an University, Yan'an, Shaanxi 716000,  People's Republic of China.
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Chen
authors.forename: Ya-Li
authors.initials: YL
authors.lastname: Qiao
authors.forename: Lou-Jun
authors.initials: LJ
authors.lastname: Gao
authors.forename: Hua-Li
authors.initials: HL
authors.lastname: Cui
authors.forename: Mei-Li
authors.initials: ML
authors.lastname: Zhang