Norbornene498-66-8100 % similar Norbornadiene121-46-033 % similar 5-Norbornen-2-ol13080-90-532 % similar Vinyl norbornene3048-64-432 % similar Bicyclo[2.2.1]hept-5-ene-2-carboxaldehyde5453-80-532 % similar 1,2,4-Trivinylcyclohexane2855-27-830 % similar