To a solution of the compound of example 64 (1.10 g, 4.19 mmol) and HOBt (0.70 g, 5.03 mmol) in DMF (5 mL) were added O-trityl hydroxylamine (1.82 g, 6.28 mmol) and DIC (800 μL), respectively. The reaction mixture was stirred for 24 h at room temperature. The reaction mixture was partitioned between HCl (1N, excess) and ethyl acetate. The aqueous phase was extracted several times with ethyl acetate. The recombined organic layer was washed with brine, saturated sodium bicarbonate, and brine. The solvent was evaporated following drying over sodium sulfate, and the crude was flashed with 20–30% ethyl acetate in hexanes. 1H-NMR(CDCl3, 400 MH: 1.42(s, 9H); 1.58, 2.14, 2.47(3 m, 7H); 3.69(s, 3H); 7.34(m, 15H); 7.88(d, broad, 1H).
