N-phenylfluorenyl-(S)-2-amino-4-pentenoic acid

t-butyl (2S,4R)-5-[N',N''-bis(benzyloxycarbonyl)guanidino]-2-N-(9-phenyl-9H-fluoren-9-yl)amino-4-N-(2-trimethylsilylethanesulfonyl)aminopentanoate

t-butyl (2S,4S)-5-[N',N''-bis(benzyloxycarbonyl)guanidino]-2-N-(9-phenyl-9H-fluoren-9-yl)amino-4-N-(2-trimethylsilylethanesulfonyl)aminopentanoate

benzyl (S)-2-Boc-amino-4-pentenoate

benzyl (S)-2-((tert-butoxycarbonyl)amino)-3-((R)-oxiran-2-yl)propanoate