Date Published: February 01, 2012
Publisher: International Union of Crystallography
Author(s): Jie Wu, Chao Huang, Guo-Qiang Li, Hai-Yan Tian, Ren-Wang Jiang.
In the crystal structure of the title compound, [Ag(NO3)(C15H8N2O2)2], tryptanthrin (indolo[2,1-b]quinazoline-6,12-dione) and silver nitrate form a 2:1 complex. The silver ion is surrounded by two tryptanthrin ligands, each coordinating through the N atoms, with Ag—N bond lengths of 2.247 (3) and 2.264 (3) Å, and an anionic nitrate ligand coordinating through two O atoms, with Ag—O bond lengths of 2.499 (3) and 2.591 (3) Å. The N—Ag—N plane and the O—Ag—O plane are roughly perpendicular, making a dihedral angle of 81.6 (2)°. In the crystal, C—H⋯O interactions between aromatic H atoms and keto and nitrate O atoms as well as π–π interactions [centroid-centroid distance = 3.706 (4) Å] give rise to a three-dimensional network.
For the biological activity of tryptanthrin, see: Yu et al. (2007 ▶); Chan et al. (2009 ▶); Bandekar et al. (2010 ▶). For the synthesis and structural modification of tryptanthrin, see: Jao et al. (2008 ▶); Kumar et al. (2011 ▶); Chen et al. (2011 ▶). For related π–π interactions in natural flavonoids, see: Jiang et al. (2002 ▶, 2009 ▶). For standard bond lengths, see: Allen et al. (1987 ▶). For bond lengths and angles in a silver nitrate complex with 4,4′-trimethylenedipiperidine, see: Kokunov et al. (2011 ▶).