Acta Crystallographica Section E (Oct 2011)
rac-(6S)-6-Hydroxy-6-{2-[2-(propan-2-ylidene)hydrazinylidene]propyl}indolo[2,1-b]quinazolin-12(6H)-one
Abstract
The chiral title compound, C21H20N4O2, crystallizes as a racemic mixture. In the crystal, molecules form centrosymmetric π-overlapping dimers [interplanar distance = 3.338 (6) Å], which are further connected along the a axis forming centrosymmetric dimers via O—H...N hydrogen bonds. C—H...O interactions are also observed. The indolo[2,1-b]quinazoline group is somewhat bent, with a small dihedral angle of 6.3 (4)° between the plane of the quinazoline system and the plane of the benzene ring of the indole moiety. The C=N—N=C atoms of the azine group is oriented almost perpendicular [84.1 (2)°] to the mean plane of the quinazoline system.