6-(2-{[18-(4,8-Dimethyl-2-oxo(1,3,6,2-dioxazaphosphaperhydroocin-6-yl))-18-oxooctadecyl]amino}acetyl)-4,8-dimethyl-1,3,6,2-dioxazaphosphaperhydroocin-2-one AIDS-104818 AIDS104818