Poly[[bis(pyridine-kappaN)copper(II)]-mu(3)-5-hydroxyisophthalato-kappa3O:O':O''].

In the title compound, Cu(C(8)H(4)O(5))(C(5)H(5)N)(2) or Cu(OH-BDC)(py)(2) (where OH-H(2)BDC is 5-hydroxyisophthalic acid and py is pyridine), the Cu atoms are coordinated by two N atoms from the pyridine ligands and by three O atoms from hydroxyisophthalate ligands in a highly distorted triangular bipyramidal environment, with Cu-O distances in the range 1.941 (4)-2.225 (5) A and Cu-N distances of 2.014 (6) and 2.046 (6) A. The Cu(OH-BDC) two-dimensional network is built up from interlocking 22-, 15- and eight-membered rings via sharing of Cu atoms and O-H...O hydrogen bonds. Consolidation of the packing structure is achieved by edge- or point-to-face C-H...pi interactions and offset or slipped pi-pi stacking interactions.