2-[3-Carboxy-2-(2-{3-methyl-2-[3-methyl-2-(3-phenyl-propionylamino)-butyrylamino]-butyrylamino}-4-oxo-4-pyrrolidin-1-yl-butyrylamino)-propionylamino]-4,4-dimethyl-pentanoic acid AIDS-188207 AIDS188207