(2R)-2-[5-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-(trifluoromethyl)pentanamido]butanoic acid

(2S)-1-{2-[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-1H-pyrazol-1-yl]acetyl}pyrrolidine-2-carboxylic acid

3-(2-{3-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]cyclobutyl}acetamido)-4,4-difluorobutanoic acid

(3S)-3-{2-[5-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)pyridin-2-yl]acetamido}butanoic acid

(3S)-3-{[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-fluorophenyl]formamido}butanoic acid

(3R)-3-[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-2-phenylacetamido]pentanoic acid

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

3-[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanoyl]-3-azabicyclo[3.1.0]hexane-1-carboxylic acid

3-{1-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]cyclopropanecarbonyl}-3-azabicyclo[3.1.0]hexane-1-carboxylic acid

(2S)-2-({3-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]-1,2-oxazol-4-yl}formamido)propanoic acid

4-({3-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]-1,2-oxazol-4-yl}formamido)-4-methylpentanoic acid