(2R)-2-[(Tert-butoxy)carbonylamino]-2-(3,4,5-trimethoxyphenyl)acetic acid

2-(4-{2-[({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)methyl]butanoyl}piperazin-1-yl)propanoic acid

3-{2-[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)cyclopentyl]acetamido}-4-methylpentanoic acid

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

3-[2-cyclobutyl-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)acetamido]-2-(cyclopropylmethyl)propanoic acid

6-{2-[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)ethoxy]acetyl}-6-azaspiro[2.5]octane-1-carboxylic acid

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

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

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

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

3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-[(1,2,3-thiadiazol-4-yl)carbamoyl]propanoic acid