Acta Crystallographica Section E (Apr 2009)
Diethyl 2,6-(2,4-dichlorophenyl)-4,8-dioxo-2,3,6,7-tetrahydro-1H,5H-2,3a,4a,6,7a,8a-hexaazacyclopenta[def]fluorene-8b,8c-dicarboxylate
Abstract
The title molecule, C28H28Cl4N6O6, is built up from four fused rings, viz. two nearly planar imidazole five-membered rings which adopt envelope conformations with the C=O groups at the flap position, and two triazine six-membered rings which adopt chair conformations. Each six-membered ring has a 2,4-dichlorobenzyl substituent attached to an N atom. In the molecule, the two ethyl groups are each disordered between two orientations in 0.784 (16)/0.216 (16) and 0.631 (10)/0.37 (10) ratios. Weak intermolecular C—H...O hydrogen bonds help to stabilize the crystal packing.