120-74-1 193277-13-3 5-Norbornene-2-carboxylic acid (8CI) AI3-51329 Bicyclo(2.2.1)hept-2-ene-5-carboxylic acid Bicyclo(2.2.1)hept-5-ene-2-carboxylic acid EINECS 204-422-8 NSC 152348 Norbornenecarboxylic acid