1-(2-fluorophenyl)-3-(3-(6-oxo-3-phenylpyridazin-1(6H)-yl)propyl)urea

(2S,3R)-3-(benzyloxy)-2-{[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)bicyclo[2.2.1]heptan-2-yl]formamido}butanoic acid

3-[N-ethyl-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-methylbutanamido]propanoic acid

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

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

2-[3-ethoxy-4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-N-methylbutanamido]acetic acid

4-[(2-ethoxyethyl)carbamoyl]-4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanoic acid

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

2-cyclopropyl-2-[(2S)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanamido]propanoic acid

4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-4-[(3-hydroxy-2-methylpropyl)carbamoyl]butanoic acid

1-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-methylbutanoyl]pyrrolidine-3-carboxylic acid