Synonyms: 5-Norbornene-2,3-dicarboxylicacid, cis-endo- (8CI); Bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid,(endo,endo)-; 2-Norbornene-5,6-endo-cis-dicarboxylic acid; 3,6-Endomethylene-D4-tetrahydrophthalic acid;5-Norbornene-endo-2,3-dicarboxylic acid;Bicyclo[2.2.1]hept-5-ene-endo-2,3-cis-dicarboxylic acid;Bicyclo[2.2.1]hept-5-ene-endo-cis-2,3-dicarboxylic acid; Carbic acid; Endicacid; Nadic acid; cis-3,6-Endomethylene-1,2,3,6-tetrahydrophthalic acid;cis-endo-Bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid;endo-Bicyclo[2.2.1]heptene-5-ene-2,3-dicarboxylic acid;endo-Methylenetetrahydrophthalic acid; endo-Norbornene-cis-5,6-dicarboxylicacid; endo-cis-5-Norbornene-2,3-dicarboxylic acid