Poly[[diaqua­bis­(μ(3)-3-carboxyl­ato-4-hy­droxy­benzene­sulfonato)­tri-μ(2)-pyrazine-tetra­silver(I)] dihydrate]

The title coordination polymer, {[Ag(4)(C(7)H(4)O(6)S)(2)(C(4)H(4)N(2))(3)(H(2)O)(2)]·2H(2)O}(n), contains two independent Ag(I) ions. One Ag(I) ion is coordinated by one O atom from a 3-carboxyl­ato-4-hy­droxy­benzene­sulfonate (L) ligand, two N atoms from two pyrazine ligands and a water mol­ecule. The other Ag(I) ion is coordinated by two O atoms from two L ligands and one N atom from a pyrazine ligand. One of the pyrazine ligands lies on an inversion center. The L and pyrazine ligands link the Ag(I) ions into polymeric layers parallel to the ac plane. The layers are connected by inter­molecular O—H⋯O hydrogen bonds. An intra­molecular O—H⋯O hydrogen bond is also present in the L ligand.