Diaqua­bis­(dihydrogen 3-aza­niumyl-1-hy­droxy­propyl­idene-1,1-di­phos­phon­ato-κ(2) O,O′)cobalt(II)

The asymmetric unit of title compound, [Co(C(3)H(10)NO(7)P(2))(2)(H(2)O)(2)], contains one half-mol­ecule of the complex. The Co(II) atom is located on an inversion centre and displays a distorted octa­hedral coordination geometry defined by four O atoms of two 3-aza­niumyl-1-hy­droxy­propyl­idene-1,1-bis­phospho­nato ligands in the equatorial plane and two water mol­ecules located in axial positions. The ligand mol­ecules, which exist in a zwitterionic state, form two six-membered chelate rings with chair conformations. In the crystal, mol­ecules are inter­linked by O—H⋯O and N—H⋯O hydrogen bonds, forming a three-dimensional supra­molecular structure.