2-{[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-hydroxybutanamido]methyl}-3-methylbutanoic acid

3-{4-[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanamido]phenyl}propanoic acid

(2S)-2-(1-{1-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]cyclopropyl}-N-methylformamido)propanoic acid

(2S)-2-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)pentanamido]-3-methylbutanoic acid

5-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)propanamido]pyridine-2-carboxylic acid

3-{1-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)propanoyl]pyrrolidin-3-yl}propanoic acid

2-{4-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-2,2-dimethylpropanoyl]piperazin-1-yl}acetic acid

1-[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3,3,3-trifluoro-2-methylpropanamido]cyclobutane-1-carboxylic acid

2-ethyl-3-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-2-methoxypropanoyl]-1,3-thiazolidine-4-carboxylic acid

3-({5-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]oxolan-2-yl}formamido)-2-methoxypropanoic acid

3-({4-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]phenyl}formamido)pentanoic acid