5a-Butyl-1,3,8,10-tetrachloro-7,13-bis(4-nitrobenzoyl)-5a,6a,12a,12b-tetrahydro-7H,13H-thieno[2,3-b:4,5-b′]bis(1,4-benzoxazine)

The title compound, C34H24Cl4N4O8S, is a linear pentacyclic system formed of two substituted benzoxazinyl groups fused to 2-n-butyltetrahydrothiophene. The oxazine ring, which is fused to the n-butyl-substituted side of the thiophene ring, is in a boat conformation. The other fused oxazine ring and the tetrahydrothiene ring are each in an envelope conformation. The bridgehead C atom α to both the S and N atoms forms the flap of each envelope. This results in a twist of the pentacyclic system such that the dihedral angle between the terminal dichlorobenzene rings is 82.92 (8)°. In the crystal, inversion-related molecules form a weakly hydrogen-bonded dimer, with two C—H...O interactions between an H atom on the oxazine ring and an amide O atom. Additionally, C—H...O interactions occur between an H atom on a screw-related nitrobenzene ring and an O atom on the nitrobenzene ring of one molecule. One of the Cl atoms and the butyl group are disordered over two sets of sites with occupancy ratios of 0.94 (2):0.06 (2) and 0.624 (4):0.376 (4), respectively.