(1S,3R,8R,9S,11R)-10,10-Di­bromo-2,2-di­chloro-3,7,7,11-tetra­methyl­tetra­cyclo­[6.5.0.0(1,3).0(9,11)]trideca­ne

The title compound, C(17)H(24)Br(2)Cl(2), was synthesized from β-himachalene (3,5,5,9-tetra­methyl-2,4a,5,6,7,8-hexa­hydro-1H-benzo­cyclo­heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The asymmetric unit contains two independent mol­ecules. Each mol­ecule is built up from fused six-, seven- and two three-membered rings. In both mol­ecules, the six-membered ring has a half-chair conformation, whereas the seven-membered ring displays a boat conformation. No specific inter­molecular inter­actions are noted in the crystal packing.