Ethyl 5,5-dichloro-3-(4-chloro-phen-yl)-3a-methyl-4a-phenyl-3a,4,4a,5-tetra-hydro-3H-aziridino[2,1-d][1,2,4]triazolo[4,3-a][1,5]benzodiazepine-1-carboxyl-ate.

In the title compound, C(27)H(23)Cl(3)N(4)O(2), the seven-membered diazepine ring adopts a boat conformation. The triazole ring makes dihedral angles of 17.24 (8) and 82.86 (8)°, respectively, with the chloro-benzene ring and the benzene ring of the benzodiazepine unit.