3-(1H-Indol-3-yl)-2-(2-nitrobenzenesulfonamido)propanoic acid including an unknown solvate

• Main Authors: Islam Ullah Khan, Hafiz Mubashar-ur-Rehman, Salman Aziz, William T. A. Harrison
• Format: Article
• Language: English
• Published: International Union of Crystallography 2012-07-01
• Series: Acta Crystallographica Section E
• Online Access: http://scripts.iucr.org/cgi-bin/paper?S1600536812023446

In the title compound, C17H15N3O6S, which crystallized with highly disordered methanol and/or water solvent molecules, the dihedral angle between the the indole and benzene ring systems is 5.3 (2)°, which allows for the formation of intramolecular π–π stacking interactions [centroid–centroid separations = 3.641 (3) and 3.694 (3) Å] and an approximate overall U-shape for the molecule. In the crystal, dimers linked by pairs of Ns—H...Oc (s = sulfonamide and c = carboxylate) hydrogen bonds generate R22(10) loops, whereas Ni—H...π (i = indole) interactions lead to chains propagating in [100] or [010]. Together, these lead to a three-dimensional network in which the solvent voids are present as intersecting (two-dimensional) systems of [100] and [010] channels. The title compound was found to contain a heavily disordered solvent molecule, which could be methanol or water or a mixture of the two. Due to its uncertain nature and the unresolvable disorder, the data were processed with the SQUEEZE option in PLATON [Spek (2009). Acta Cryst. D65, 148–155], which revealed 877.8 Å3 of solvent-accessible volume per unit cell and 126 electron-units of scattering density or 109.7 Å3 (16 electron units) per organic molecule.. This was not included in the calculations of overall formula weight, density and absorption coefficient.