(S)-1-((S)-4-(benzyloxy)-3-(((S)-4-(benzyloxy)-3-hydroxy-4-oxobutyl)amino)-4-oxobutyl)azetidine-2-carboxylic acid

3”-O-叔-丁基-2’-脱氧麦根酸叔-丁基二乙酯

benzyl 4-((2-oxotetrahydrofuran-3-yl)amino)-2-((tetrahydro-2H-pyran-2-yl)oxy)butanoate

benzyl 4-((tert-butoxycarbonyl)(2-oxotetrahydrofuran-3-yl)amino)-2-((tetrahydro-2H-pyran-2-yl)oxy)butanoate

benzyl 4-((1-(benzyloxy)-4-hydroxy-1-oxobutan-2-yl)(tert-butoxycarbonyl)amino)-2-((tetrahydro-2H-pyran-2-yl)oxy)butanoate