(2S)-2-[[(2S)-2-acetamido-4-hydroxy-4-oxobutanoyl]amino]-6-hydrazinylheptanedioic acid
(2S)-2-[[(2S)-2-acetamido-4-hydroxy-4-oxo-butanoyl]amino]-6-hydrazino-heptanedioic acid
(2S)-2-[[(2S)-2-acetamido-4-hydroxy-1,4-dioxobutyl]amino]-6-hydrazinoheptanedioic acid
(2S)-2-[[(2S)-2-acetamido-4-hydroxy-4-keto-butanoyl]amino]-6-hydrazino-pimelic acid
(2S)-2-[[(2S)-2-acetamido-4-hydroxy-4-oxo-butanoyl]amino]-6-hydrazinyl-heptanedioic acid