Synthesis of PRP 15. Reagents and conditions: a) NH2OH, Na2CO3, 1:1 MeOH/H2O, Reflux, 4 h; b) trifluoroacetic anhydride, 0→50 °C, pyridine, 5 h; c) (Boc)2O, CHCl3, 0 °C→rt; d) 1. perfluorobenzaldehyde, DCM, 8 h, 2. NaBH4, CH3OH, 0 °C–rt, 3 h; e) propargyl bromide, K2CO3, CH3CN, 48 h; f) HCl, 1,4-dioxane, 1 h; g) EDC•HCl, HOBt, DMAP, Et3N, CHCl3, 12 h; h) NaN3, Bu4NN3, DMF, 80 °C, 18 h.