2-Ethylbutanoyl-Tbg-NHCH(2-oxononyl)-CO-Asp-Leu-OH AIDS-164984 AIDS164984 L-Leucine, N-[2-[[(2S)-2-[(2-ethyl-1-oxobutyl)amino]-3,3-dimethyl-1-oxobutyl]amino]-1,4-dioxoundecyl]-L-.alpha.-aspartyl-