5,12-Dimethyl­pyrazino­[1,2-a:4,5-a′]dibenzimidazole-5,12-diium dichloride dihydrate

The title hydrated salt, C₁₈H₁₈N₄²⁺·2Cl⁻·2H₂O, sits about an inversion centre, such that the asymmetric unit contains one half-mol­ecule. In the crystal, hydrogen bonds occur between the water mol­ecules and chloride anions, and there is π–π stacking of the benzene and imidazole rings of inversion-related pairs of mol­ecules, with a centroid–centroid distance of 3.704 (17) Å.

3-(4-Meth­oxy­phen­yl)-6,7-dihydro-1H-furo[3,4-c]pyran-4(3H)-one

In the title compound, C₁₄H₁₄O₄, the dihedral angle between the hydro­furan and benzene rings is 88.41 (15)°. The hydro­pyran ring adopts an envelope conformation, with the O-bound methyl­ene C atom as the flap. In the crystal, weak aromatic π–π stacking is observed [centroid–centroid separation = 3.848 (2) Å].