(S)-19-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)-2,2-dimethyl-4,13-dioxo-3,8,11-trioxa-5,14-diazaicosan-20-oic acid 1g

(S)-19-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)-2,2-dimethyl-4,13-dioxo-3,8,11-trioxa-5,14-diazaicosan-20-oic acid 1g