ethyl 2-methyl-1-propan-2-ylcyclopentane-1-carboxylate

ethyl 3-propan-2-ylcyclopentene-1-carboxylate

ethyl 2-hydroxy-3-propan-2-ylcyclopentane-1-carboxylate

(9ci)-3-(1-甲基乙基)-1-环戊烯-1-羧酸

ethyl 2-oxo-3-propan-2-ylcyclopentane-1-carboxylate