Synonyms: 5-Norbornene-2,3-dicarboxylicacid, 1,4,5,6,7,7-hexachloro- (6CI,8CI);1,4,5,6,7,7-Hexachloro-5-norbornene-2,3-dicarboxylicacid;1,4,5,6,7,7-Hexachlorobicyclo-(2,2,1)hept-5-en-2,3-dicarboxylic acid;1,4,5,6,7,7-Hexachlorobicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid;1,4,5,6,7,7-Hexachlorodicyclo-(2.2.1)-5-heptene-2,3-dicarboxylic acid;2H,3H-Hexachlorobicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid;HET acid;Hexachloroendomethylenetetrahydrophthalicacid;NSC 22231;NSC 41876;