%0 Journal Article
%T Bis[8-ethyl-5-oxo-2-(piperazin-4-ium-1-yl)-5,8-dihydropyrido[2,3-d]pyrimidine-6-carboxylic acid] 2,5-dicarboxybenzene-1,4-dicarboxylate octahydrate
%A Guang-Ju Zhang
%A Jiang-Hong He
%A Shi-Wei Yan
%A Zhong-Li Ye
%J Acta Crystallographica Section E
%D 2011
%I International Union of Crystallography
%R 10.1107/s1600536811011068
%X The asymmetric unit of the title compound, 2C14H18N5O3+¡¤C10H5O82 ¡¤8H2O, contains one [H2ppa]+cation, one half of an [H2btec]2  anion (H4btec = 1,2,4,5-benzenetetracarboxylic acid and Hppa = 8-ethyl-5-oxo-2-piperazin-1-yl-5,8-dihydropyrido[2,3-d]pyrimidine-6-carboxylic acid) that is completed by inversion symmetry and four water molecules. In the crystal, the molecules are connected by intermolecular hydrogen-bonding interactions and ¦Ð¨C¦Ð stacking between the benzene rings of the [H2btec]2  anion and the pyrimidine rings of the [H2ppa]+ cation [centroid¨Ccentroid distance = 3.597 (3)  ], generating a three-dimensional supramolecular structure.
%U http://scripts.iucr.org/cgi-bin/paper?S1600536811011068