Reaction Steps
O-Propargyl Boc-Puromycin 4 (480 mg, 0.81 mmol) was dissolved in a 1:1 TFA (4 mL) and CH2Cl2 (4 mL) mixture and then stirred at room temperature for 30 min. Volatiles were evaporated in vacuo and the residue was dissolved in CH2Cl2. The solution was poured into saturated aqueous NaHCO3. The organic layer was dried over Na2SO4 and evaporated to dryness in vacuo. The residue was purified by flash chromatography (SiO2, step-wise gradient from 5-15% MeOH in CH2Cl2) to afford the O-propargyl-puromycin 5 (111 mg, 28%) as a white solid. 1H NMR (600 MHz, DMSO-d6): δ 8.44 (s, 1H), 8.24 (s, 1H), 8.06 (br, 1H), 7.17 (d, J=8.4 Hz, 2H), 6.90 (d, J=8.4 Hz, 2H), 6.13 (d, J=5.4 Hz, 1H), 5.98 (d, J=3.0 Hz, 1H), 5.13 (t, J=5.4 Hz, 1H), 4.74 (d, J=1.8 Hz, 2H), 4.42-4.51 (m, 2H), 3.91-3.96 (m, 1H), 3.66-3.72 (m, 1H), 3.26-3.58 (m, 9H), 2.92 (dd, J=14.4, 4.8 Hz, 1H), 2.52-2.58 (m, 1H), 2.02 (br, 2H); 13C NMR (150 MHz, DMSO-d6): δ 174.6, 155.7, 154.3, 151.8, 149.6, 137.9, 131.3, 130.2, 119.6, 114.5, 89.4, 83.5, 79.4, 78.0, 73.2, 61.0, 56.1, 55.3, 50.0, 40.4, 40.0; HRMS: (ESI, m/z) calcd [M+H]+ for C24H29N7O5: 496.2303. found 496.2308.
