Aqua­[1-(pyrazin-2-yl)ethanone oximato-κ²N,N′][1-(pyrazin-2-yl)ethanone oxime-κ²N,N′](thio­cyanato-κN)nickel(II)

In the title complex, [Ni(C₆H₆N₃O)(NCS)(C₆H₇N₃O)(H₂O)] or [Ni(mpko)(SCN)(mpkoH)(H₂O)] [where mpkoH = 1-(pyrazin-2-yl)ethanone oxime], the Ni^II cation is in a slightly distorted octa­hedral geometry, being coordinated in the equatorial plane by four N atoms from two different mpkoH ligands, one of which is deprotonated, and by one N atom from a thio­cyanate anion and one O atom from a water mol­ecule in the axial positions. There is an intra­molecular O—H...O hydrogen bond involving the oxime units of the two ligands. In the crystal, a three-dimensional supra­molecular architecture is formed by O—H...O and O—H...N hydrogen bonds.

Dimethyl 2,2′-[2,2′-bi(1H-1,3-benzimidazole)-1,1′-di­yl]diacetate

The whole mol­ecule of the title compound, C₂₀H₁₈N₄O₄, is generated by an inversion center. The benzimidazole ring mean plane make a dihedral angle of 89.4 (8)° with the plane passing through the acetate group (COO). In the crystal, mol­ecules are linked via weak C—H...O hydrogen bonds and π–π inter­actions [centroid–centroid distance = 3.743 (3) Å] involving inversion-related benzimidazole groups.