(S)-4-bromo-3-hydroxybutyric acid ethyl ester

(R)-(+)-4-溴-3-羟基丁酸乙酯

1,4-环己二酮-2,5-二甲酸二乙酯

4-甲氧基乙酰乙酸乙酯

2-氨基-4-噻唑乙酸乙酯