3,6-Endomethylene-.DELTA.4-tetrahydrophthalic acid 3853-88-1 5-Norbornene-2,3-dicarboxylic acid, cis-endo- Bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid, (endo,endo)- Carbic acid Endic acid NSC123024 Nadic acid endo-Methylenetetrahydrophthalic acid endo-Norbornene-cis-5,6-dicarboxylic acid