AIDS-153853 AIDS153853 [(1S,2R)-1-Benzyl-2-hydroxy-3-(2-oxo-15-phenyl-1-oxa-3-aza-cyclopentadec-3-yl)-propyl]-carbamic acid, (3R,3aS,6aR)-(hexahydro-furo[2,3-b]furan-3-yl) ester