Reaction Steps
To a solution of 3′-O-tert-butyldimethylsilyl-2′-deoxy-5′-O—[N-(2-hydroxybenzoyl)sulfamoyl]-adenosine (10.5 mg, 0.018 mmol, 1.0 equiv) in THF (2.0 mL) was added TBAF (1.0 M solution in THF, 0.1 mL, 6.0 equiv) and the solution stirred 3 hours at room temperature. The reaction mixture was concentrated and purification of the residue by flash chromatography (65:35:1 EtOAc/MeOH/Et3N) afforded the title compound (5.1 mg, 50%): Rf 0.15 (3:1 EtOAc/MeOH); [α]20D −99 (c 0.25, CH3OH) 1H NMR (600 MHz, CD3OD) δ 1.29 (t, J=7.2 Hz, 9H), 2.44 (ddd, J=13.8, 5.4, 2.4 Hz, 1H), 2.70-2.90 (m, 1H), 3.18 (q, J=7.2 Hz, 6H), 4.24 (s, 1H), 4.32 (dd, J=11.4, 3.6 Hz, 1H), 4.35 (dd, J=10.8, 3.6 Hz, 1H), 4.62-4.70 (m, 1H), 6.50 (t, J=6.6 Hz, 1H), 6.75-6.84 (m, 2H), 7.29 (t, J=7.8 Hz, 1H), 7.93 (d, J=7.8 Hz, 1H), 8.16 (s, 1H), 8.50 (s, 1H); 13C NMR (150 MHz, CD3OD) δ 9.4, 41.6, 48.1, 70.0, 73.5, 85.9, 87.0, 118.0, 119.4, 120.3, 120.8, 131.5, 134.5, 141.3, 150.6, 153.9, 157.4, 162.2, 175.1; HRMS (ESI+) calcd for C17H19N6O7S [M+H]+ 451.1030, found 451.1014 (error 3.5 ppm).
