aReagents and conditions: (a) BH3·THF, Bu2BOTf, CH2Cl2 0 °C, and 91%; (b) AcSH, pyridine/CHCl3, RT, and 84%; (c) N3(CH2CH2O)3Ts, NaH, DMF, 0 °C ~ RT, 10, 89%, 15, and 73%; (d) NaBrO3, NaS2O4, EtOAc/H2O, RT, and 90%; (e) DMC, Et3N, H2O, 0 °C, 12, 90%, 17, and 85%; (f) AcSH, pyridine/CHCl3, 60 °C, and 85%; (g) TFA, CH2Cl2, −20–0 °C, and 82%; (h) Pd/C, H2, HCl (aq), THF/H2O, then, TfN3, K2CO3, CuSO4, CH2Cl2/MeOH/H2O, RT, and 66%.