2,4-dimethyl-1-propan-2-ylcyclopenta-1,3-diene;1-isopropyl-2,4-dimethyl-cyclopenta-1,3-diene;1-isopropyl-2,4-dimethylcyclopenta-1,3-diene;2,4-dimethyl-1-propan-2-yl-cyclopenta-1,3-diene
2,4-dimethyl-1-propan-2-ylcyclopenta-1,3-diene