Two hydrates of 2,6-bis(1H-benzimidazol-2-yl)pyridine

The structures of the mono- and sesquihydrates of 2,6-bis(1H-benzimidazol-2-yl)pyridine (bbip) are reported. Phase (I), C(19)H(13)N(5).H(2)O, has one water and one bbip molecule in the asymmetric unit, while phase (II), C(19)H(13)N(5).1.5H(2)O, has three water molecules and two bbip molecules in the asymmetric unit. The compounds exhibit very similar molecular geometries but different packing organizations, which result from intricate hydrogen-bonding schemes.