6,10-dimethyl-9-methylideneundec-5-en-2-one

2,6-dimethyl-9-(2-methyl-1,3-dioxolan-2-yl)non-6-en-3-one

methyl 2-methyl-6-oxohept-2-enoate

甲基1-甲基-2-亚甲基-3-环戊烯-1-羧酸酯

methyl 2-methyl-6-oxohex-2-enoate