Acta Cryst. (2013). E69, o1027 [ doi:10.1107/S1600536813014463 ]
Abstract: The co-crystal, C7H9N4O2+·ClO4-·C20H24O6·3.25H2O, consists of theobrominium (3,7-dimethyl-2,6-dioxo-1H-purin-9-ium) cations, perchlorate anions and dibenzo-18-crown-6 and water molecules. The crown ether is in a bent conformation, in which the planes of the aromatic rings subtend an angle of 63.7 (1)°. Intermolecular O-HO hydrogen bonding between the water molecules and the O atoms of the cyclic ether delimit an empty space reminiscent of a hollow cage. The water molecules are additionally linked to the cations by N-HO hydrogen bonding. One of the positions of the water molecules is occupied only fractionally (25%) and is located outside this framework.
Copyright © International Union of Crystallography