ethyl (3S)-3,4-dihydroxy-3,4-O-isopropylidene-butanoate

3,5-dinitrobenzoate of (3S)-3,4-(isopropylidenedioxy)butan-1-ol

L-苹果酸

L-苹果酸二甲酯

(E)-ethyl 4-((S)-2,2-dimethyl-1,3-dioxolan-4-yl)but-2-enoate