((S)-1-{(1S,2R)-1-Benzyl-3-[(S)-2-(tert-butylcarbamoyl-methyl)-3,3-dimethyl-butanoylamino]-2-hydroxy-propylcarbamoyl}-2-methyl-propyl)-carbamic acid benzyl ester (OHEt)amide isostere AIDS-050390 AIDS050390