d-Phenylalaninal

(2S)-2-[3-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-2,2-difluoropropanamido]-4-methoxy-4-oxobutanoic acid

2-[N-cyclopropyl-2-(ethyl carboxy)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)acetamido]acetic acid

7-[(2S)-4-(benzyloxy)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-4-oxobutanoyl]-7-azabicyclo[2.2.1]heptane-2-carboxylic acid

(1RS,2SR)-2-{[(2S)-3-(benzyl carboxy)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)propanamido]methyl}cyclopentane-1-carboxylic acid

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

1-[3-ethoxy-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3-oxopropanoyl]azetidine-3-carboxylic acid

(2R)-2-{[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)cyclopentyl]formamido}-4-methoxy-4-oxobutanoic acid

(2R)-2-[(2S)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-3,3-dimethylbutanamido]-4-methoxy-4-oxobutanoic acid

(2R)-2-[(2S)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)hexanamido]-4-methoxy-4-oxobutanoic acid

(2R)-2-[2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-2-(methoxymethyl)propanamido]-4-methoxy-4-oxobutanoic acid