(4R)-N-(tert-Butyl)-3-[(2S,3S)-2-hydroxy-3-({N-[(1-naphthyloxy)acetyl]-L-threonyl}amino)-4-phenylbutanoyl]-1,3-thiazolidine-4-carboxamide 1Nap-O-CH2CO-Thr-(2S,3S)-AHPBA-Thz-NH-tBu AIDS-163712 AIDS163712