2,4-二氨基丁酸

(3R,5S,6R)-4-[(benzyloxy)carbonyl]-3-(O,O'-dibenzylmalonyl)-5,6-diphenyl-2,3,5,6-tetrahydro-2H-1,4-oxazin-2-one

草酰乙酸

2-氨基乙烷-1,1,2-三羧酸

ethyl 1-cyclohexanecarbonyl-4-oxo-2-azetidinecarboxylate