123951-86-0 AIDS-000528 AIDS000528 Butanoic acid, L-threonyl-L-threonyl-L-asparaginyl-L-tyrosyl-L-2-amino- H-Thr-Thr-Asn-Tyr-.alpha.-Aminobutyric acid-OH H-Thr-Thr-Asn-Tyr-Abu-OH