6-Cyclopropyl-4-[4-(3,3-dimethyl-4-oxoazetidin-2-yl)piperidine-1-carbonyl]-1H-pyridin-2-one

4-(3-cyanopiperidin-1-yl)-3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-4-oxobutanoic acid

(2S)-2-{[(1RS,3RS,5RS)-3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)bicyclo[3.1.0]hexan-1-yl]formamido}-3-methylpentanoic acid

rac-2-{[(1R,3R,5R)-3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)bicyclo[3.1.0]hexan-1-yl]formamido}pent-4-enoic acid

4-({1-[(tert-butoxy)carbonyl]-3-cyanopiperidin-4-yl}({[(9H-fluoren-9-yl)methoxy]carbonyl})amino)butanoic acid

2-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-N-methylpentanamido]benzoic acid

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

4-({1-[(tert-butoxy)carbonyl]-2-phenylpiperidin-4-yl}({[(9H-fluoren-9-yl)methoxy]carbonyl})amino)butanoic acid

rac-(1R,3R)-3-[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-methylbutanamido]cyclohexane-1-carboxylic acid

2-[({2-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]cyclopropyl}formamido)methyl]pyridine-4-carboxylic acid

3-{3-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]-1,2-oxazole-4-amido}cyclobutane-1-carboxylic acid