(2R,3S)-N-((1S,2S)-2-((R)-2-((S)-2-(2-naphthamido)propanamido)-4-phenylbutyl)cyclopropyl)-3-((S)-sec-butyl)-4-oxooxetane-2-carboxamide

(2R,3S)-N-((1S,2S)-2-((R)-2-((S)-2-aminopropanamido)-4-phenylbutyl)cyclopropyl)-3-((S)-sec-butyl)-4-oxooxetane-2-carboxamide 2,2,2-trifluoroacetate