Crystal structure of 5-amino-5′-chloro-6-(4-chlorobenzoyl)-8-nitro-2,3-dihydro-1H-spiro[imidazo[1,2-a]pyridine-7,3′-indolin]-2′-one including an unknown solvent molecule
The asymmetric unit of the title compound, C21H15Cl2N5O4, contains two independent molecules (AandB) having similar conformations. The amine (NH2) group forms an intramolecular hydrogen bond with the benzoyl group, giving anS(6) ring motif in both molecules. The central six-membered rings adopt sofa conformations and the imidazole rings are planar (r.m.s deviations = 0.0150 and 0.0166 Å). The pyridine and imidazole rings are inclined to one another by 3.54 (1) and 3.03 (1)° in moleculesAandB, respectively. In the crystal, molecules are linked by N—H...O hydrogen bonds, forming chains along theaaxis which encloseR22(16) ring motifs. The rings are linked by weak N—H...O and C—H...O hydrogen bonds and C—H...π interactions forming sheets lying parallel to (001). A region of disordered electron density, most probably disordered solvent molecules, occupying voids ofca753 Å3for an electron count of 260, was treated using the SQUEEZE routine inPLATON[Spek (2009).Acta Cryst.D65, 148–155]. Their formula mass and unit-cell characteristics were not taken into account during refinement.