3PhS-6Ph-2-Pyranone, 6-cyclic amide deriv. AIDS-032668 AIDS032668 tert-Butyl 4-(3-{4-hydroxy-5-[(2-isopropylphenyl)thio]-6-oxo-2-phenyl-3,6-dihydro-2H-pyran-2-yl}propanoyl)piperazine-1-carboxylate