反应详情

To a stirred mixture of Compound 249A (1.40 g, 6.47 mmoL) in 10 mL of CH2Cl2 was added Et3N (1.08 mL, 7.76 mmoL), followed by Cbz-OSu (1.69 g, 6.80 mmoL). The reaction mixture was stirred at room temperature for 16 hrs and then diluted with 300 mL of EtOAc. The organic layer was washed with 5% citric acid solution (2×40 mL), 5% K2CO3 solution (2×40 mL) and brine (40 mL) and dried (MgSO4). The residue was filtered and concentrated in vacuo to afford 2.25 g (yield: 99%) of Compound 262A. It had an analytical HPLC retention time=3.02 min. (Phenomenox S5 C18-HC 4.6×50 mm column, 10–90% aqueous methanol over 4 minutes containing 0.1% TFA, 4 ml/min, monitoring at 220 nm) and a LC/MS M++1=351.

1. washThe organic layer was washed with 5% citric acid solution (2×40 mL), 5% K2CO3 solution (2×40 mL) and brine (40 mL)
2. dry with materialdried (MgSO4)
3. filtrationThe residue was filtered
4. concentrationconcentrated in vacuo