1(2H)-Pyrimidineacetamide, N-[(1S,3S,4S)-4-[[2-[(2,4-dimethyl-3-pyridinyl)oxy]acetyl]amino]-3-hydroxy-5-phenyl-1-(phenylmethyl)pentyl]tetrahydro-.alpha.-(1-methylethyl)-2-oxo-, (a1S)- AIDS-121171 AIDS121171