12-Amino-5-benzyl-15,18,21,24,27-pentakis(4-((2-(((benzyloxy)carbonyl)amino)-3-phenylpropanoyl)amino)butyl)-3,6,13,16,19,22,25-heptaoxo-1-phenyl-2-oxa-4,7,14,17,20,23,26-heptaazaoctacosan-28-oic acid AIDS-144912 AIDS144912 NSC668437