3-(1-Ethynyl)-4-(4-nitrophenoxy)-2-pyridinamine

2-{[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)cyclobutyl]formamido}hex-4-ynoic acid

2-{[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)hex-4-ynamido]oxy}acetic acid

2-[(2S)-1-{2-[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)acetamido]acetyl}pyrrolidin-2-yl]acetic acid

(3aRS,7aRS)-2-[(2S)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanoyl]-octahydropyrano[3,4-c]pyrrole-7a-carboxylic acid

(3aRS,7aRS)-2-[(2R)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanoyl]-octahydropyrano[3,4-c]pyrrole-7a-carboxylic acid

rac-(3aR,7aR)-2-[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanoyl]-octahydropyrano[3,4-c]pyrrole-7a-carboxylic acid

rac-(3aR,7aR)-2-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanoyl]-octahydropyrano[3,4-c]pyrrole-7a-carboxylic acid

3-{[(3-ethoxycyclobutyl)methyl]carbamoyl}-3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)propanoic acid

4-{[(3-ethoxycyclobutyl)methyl]carbamoyl}-4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)butanoic acid

2-{[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-N,4,4-trimethylpentanamido]oxy}acetic acid