(S)-2-[(1R,2S)-2-Acetoxy-1-(4-methoxy-benzyloxy)-3-oxo-propyl]-aziridine-1-carboxylic acid benzyl ester

(S)-2-[(Z)-(1R,2R)-2-Acetoxy-4-acetylamino-1-(4-methoxy-benzyloxy)-4-methoxycarbonyl-but-3-enyl]-aziridine-1-carboxylic acid 9H-fluoren-9-ylmethyl ester

(E)-(4S,5R)-4-Acetoxy-2-acetylamino-5-(S)-aziridin-2-yl-3-bromo-5-(4-methoxy-benzyloxy)-pent-2-enoic acid methyl ester