1-acetoxy-2-(6-carbethoxyhexyl)-1-cyclopentene

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

水

ethyl 2-(6-carbethoyxhexyl)cyclopentanone-5-glyoxalate

5-(5-oxocyclopenten-1-yl)pentyl acetate