AIDS-057821 AIDS057821 Boc-Phe[CH(OH)CH2NH]Phe-Glu-Phe-NH2 N-{(2R,3S)-3-[(tert-Butoxycarbonyl)amino]-2-hydroxy-4-phenylbutyl}-L-phenylalanyl-L-.alpha.-glutamyl-L-phenylalaninamide