1,2,3,4,7,7-Hexachloro-2,5-norbornadiene 1,2,3,4,7,7-Hexachlorobicyclo[2.2.1]hepta-2,5-diene 1,2,3,4,7,7-Hexachloronorbornadiene 2,5-Norbornadiene, 1,2,3,4,7,7-hexachloro- 3389-71-7 Bicyclo[2.2.1]hepta-2,5-diene, 1,2,3,4,7,7-hexachloro- Hexachloronorbornadiene NSC46471