7,7-Dimethyl-3a,3b,4,5,7,7a-hexahydro-pentaleno[1,2-c]furan-1,3-dione

异丙亚基环戊烷

1-(1-Methylethenyl)cyclopentene

3-ethenyl-4-methylpenta-1,3-diene

(Z)-2-methyl-3-vinylpenta-1,3-diene