catena-Poly[[aqua­(dipyrido[3,2-a:2′,3′-c]phenazine-κ(2) N (4),N (5))zinc(II)]-μ-pyrazine-2,3-dicarboxyl­ato-κ(3) N (1),O (2):O (3)]

In the title compound, [Zn(C(6)H(2)N(2)O(4))(C(18)H(10)N(4))(H(2)O)](n) or [Zn(PZDC)(DPPZ)(H(2)O)](n) (where DPPZ is dipyrido[3,2-a:2′,3′-c]phenazine and H(2)PZDC is pyrazine-2,3-dicarboxylic acid), the Zn atom is six-coordinated in a slightly distorted octa­hedral coordination geometry by three N atoms from one DPPZ ligand and one PZDC(2−) dianion, three O atoms from two different PZDC(2−) ligands and one water mol­ecule. Each PZDC(2−) dianion serves as a spacer, connecting adjacent metal atoms into a polymeric chain structure parallel to the b axis. The chain motif is consolidated into a three-dimensional supra­molecular network by O—H⋯O and O—H⋯N hydrogen bonds and π–π aromatic stacking inter­actions involving adjacent DPPZ ligands and PZDC(2−) dianions with centroid–centroid separations of 3.522 (6) and 3.732 (8) Å, respectively.