乙基5-氧代-1-环戊烯-1-羧酸酯

ethyl 9-(5-oxocyclopenten-1-yl)nonanoate

9,12-dioxododecanoic acid

ethyl 1-(7-ethoxy-7-oxoheptyl)-2-oxocyclopentane-1-carboxylate

5-氧代环戊-1-烯-1-庚酸