diethyl 2-[2-(dibenzylamino)ethyl]-3-oxobutanedioate

5-甲基-5-己烯酸乙酯

ethyl 4-(3-methylidene-2-oxo-1-oxaspiro[4.5]decan-4-yl)butanoate

2-乙基己二酸

γ-丁内酯