3-[N-(3-{(4R)-4-[N-(tert-Butyl)carbamoyl]-5,5-dimethyl(1,3-thiazolidin-3-yl)}(1S,2S)-2-hydroxy-3-oxo-1-benzylpropyl)carbamoyl]-2-methylbutanoic acid AIDS-033442 AIDS033442 Aspns-Thz-NH-t-Bu deriv. KNI-549