(10S,13S,1'R)-13-[1'-Hydroxy-2'-(N-p-aminobenzenesulfonyl-1''-amino-3''-methylbutyl)ethyl]-8,11-dioxo-10-isopropyl-2-oxa-9,12-diazabicyclo[13.2.2]nonadeca-15,17,18-triene AIDS-051275 AIDS051275 Macrocylic deriv.