1,1-Dimethylethyl N-[4-(2,6-dichloro-3-aminobenzamido)-1,4-dibenzyl-3-hydroxybutyl]carbamate 2,6-diCl 3NH2 N-OHBu-BzNH, PhCH2 Boc deriv. AIDS-028157 AIDS028157 Benzamide hydroxyethyl analog