(2R,3S,4R,5S)-N-(tert-butoxycarbonyl)-2-[(2-naphthalen-1-ylamino)ethyl]-3,4-O-isopropylidene-5-methylpyrrolidine-3,4-diol

(2R,3S,4R,5S)-N-(tert-butoxycarbonyl)-2-[(1,1'-biphenyl-4-carbamoyl)methyl]-3,4-O-isopropylidene-5-methylpyrrolidine-3,4-diol