2-((3-(tert-butoxy)-3-oxopropyl)amino)acetic acid

3,6,9,12-tetrakis(3-(tert-butoxy)-3-oxopropyl)-15-((3-(tert-butoxy)-3-oxopropyl)glycyl)-20,20-dimethyl-4,7,10,13,18-pentaoxo-19-oxa-3,6,9,12,15-pentaazahenicosanoic acid