a(a) Benzyl bromide, NaH, tetra-n-butylammonium iodide, N,N-dimethylformamide (DMF), 0 °C, RT, 12 h (90%); (b) glacial acetic acid, HCl, 85 °C, 7 h (45%); (c) t-butyl 2-bromoacetate, KOH, TBAB, toluene, 0 °C, RT, 1 h (85%); (d) TFA, dichloromethane (DCM), RT, 45 min (83%); (e) NHS, N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide (EDAC), DCM, 24 h (90%); (f) DPPE-NH2, triethylamine, DMF, 16 h (88%); and (g) Pd/C, H2, THF/MeOH, 24 h (quantitative yield).