catena-Poly[[(μ-3-hy­droxy­benzoato-κ(3) O (1),O (1′):O (3))(μ-3-hy­droxy­benzoato-κ(3) O (1),O (1′):O (1))(isonicotinamide-κN (1))­lead(II)] monohydrate]

In the crystal of the title polymeric compound, {[Pb(C(7)H(5)O(3))(2)(C(6)H(6)N(2)O)]·H(2)O}(n), the Pb(II) ion is chelated by two carboxyl­ate groups of 3-hy­droxy­benzoate (HB) anions, and coordinated by one isonicotinamide mol­ecule; a carboxyl­ate O atom and a hy­droxy O atom from adjacent HB anions bridge the Pb(II) ion to form polymeric chains along [100], in which the Pb(II) ion is in an irregular seven-coordination geometry. The carboxyl­ate groups of the HB ions are slightly twisted away from the attached benzene rings by 2.84 (15) and 4.8 (2)°. The planes of the two benzene rings of the HB ions are oriented with respect to each other at a dihedral angle of 84.41 (8)°. In the crystal, adjacent polymeric chains inter­act via O—H⋯O, N—H⋯O and weak C—H⋯O hydrogen bonds. The solvent water mol­ecule links with the polymeric chains via O—H⋯O hydrogen bonding. π–π stacking between the benzene and pyridine rings and between the benzene rings [centroid–centroid distances = 3.731 (2) and 3.353 (2) Å] are present in the crystal.