5,8-Bis[bis(pyridin-2-yl)amino]-1,3,4,6,7,9,9b-heptaazaphenalen-2(1H)-one dimethyl sulfoxide monosolvate dihydrate

• Main Authors: Anke Schwarzer, Edwin Kroke
• Format: Article
• Language: English
• Published: International Union of Crystallography 2014-04-01
• Series: Acta Crystallographica Section E
• Online Access: http://scripts.iucr.org/cgi-bin/paper?S1600536814005698

In the asymmetric unit of the title compound, C26H17N13O·C2H6OS·2H2O, there is one independent heptazine-based main molecule, one dimethyl sulfoxide molecule and two water molecules as solvents. The tri-s-triazine unit is substituted with two dipyridyl amine moieties and a carbonylic O atom. As indicated by the bond lengths in this acid unit of the heptazine derivative [C=O = 1.213 (2) Å, while the adjacent C—N(H) bond = 1.405 (2) Å] it is best described by the keto form. The cyameluric nucleus is close to planar (r.m.s. deviation = 0.061 Å) and the pyridine rings are inclined to its mean plane by dihedral angles varying from 47.47 (5) to 70.22 (5)°. The host and guest molecules are connected via N—H...O, O—H...O and O—H...N hydrogen bonds, forming a four-membered inversion dimer-like arrangement enclosing an R44(24) ring motif. These arrangements stack along [1-10] with a weak π–π interaction [inter-centroid distance = 3.8721 (12) Å] involving adjacent pyridine rings. There are also C—H...N and C—H...O hydrogen bonds and C—H...π interactions present within the host molecule and linking inversion-related molecules, forming a three-dimensional structure.