N-(1,4-dimethyl-6-oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-b]pyridin-3-yl)-6-oxo-1,6-dihydropyridine-3-carboxamide

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

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

5-[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-hydroxybutanamido]-2-methylbenzoic acid

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

3-chloro-4-[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-hydroxybutanamido]benzoic acid

2-chloro-6-[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-hydroxybutanamido]benzoic acid

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

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

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

4-[4-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-hydroxybutanamido]oxolane-3-carboxylic acid