1: 61 percent / EDC; HOBt; N-ethylmorpholine 2: LiOH 3: aq. HCl / acetic acid 4: pentafluorophenyl diphenylphosphinate; N-ethylmorpholine / dimethylformamide 5: TBAF; MS 4A / tetrahydrofuran / 24 h 6: 88 percent / TPAP; NMO; MS 4A / CH2Cl2 View Scheme