2,5-dioxopyrrolidin-1-yl (1-isopropyl-4-nitro-2-oxo-2,5-dihydro-1H-pyrrol-3-yl)glycinate

Boc-D-丙氨酸-OSu

1-[(2,5-dioxopyrrolidinyl)oxycarbonyloxy]ethyl 2-methylpropanoate

3-氯苯甲酸

1-(1-氧代丙氧基)-2,5-吡咯烷二酮