N-[(2S)-3-(3-{(2R)-2-[(tert-butoxycarbonyl)amino]propyl}phenyl)-2-methylpropanoyl]-L-alanyl-N-[(1R)-3-tert-butoxy-1-(4-methoxyphenyl)-3-oxopropyl]-N-methyl-D-tryptophanamide

N-(tert-butoxycarbonyl)-L-alanyl-N-[(1R)-3-tert-butoxy-1-(4-methoxyphenyl)-3-oxopropyl]-N-methyl-D-tryptophanamide

methyl (6S,9R,12S,13S)-9-((1H-indol-3-yl)methyl)-12-(4-(((tert-butyldimethylsilyl)oxy)methyl)phenyl)-13-methoxy-2,2,6,8-tetramethyl-4,7,10-trioxo-3-oxa-5,8,11-triazatetradecan-14-oate

methyl (6S,9R,12S,13S)-9-((1H-indol-3-yl)methyl)-12-(4-(2-((tert-butyldimethylsilyl)oxy)ethyl)phenyl)-13-methoxy-2,2,6,8-tetramethyl-4,7,10-trioxo-3-oxa-5,8,11-triazatetradecan-14-oate

methyl (6S,9R,12S,13S)-9-((1H-indol-3-yl)methyl)-12-(4-cyanophenyl)-13-methoxy-2,2,6,8-tetramethyl-4,7,10-trioxo-3-oxa-5,8,11-triazatetradecan-14-oate