4.1.26 N-{[(4R,6R)-6-(6-amino-9H-purin-9-yl)-2,2-dimethyl-tetrahydro-2H-furo[3,4-d] [1,3]dioxol-4-yl]methyl}-N-(2-{[(2R,5R)-2-(6-amino-9H-purin-9-yl)-4-[(tert-butyldimethylsilyl)oxy]-5-{[(tert-butyldimethylsilyl)oxy]methyl}oxolan-3-yl]oxy}ethyl)-4-methoxy-2-nitrobenzene-1-sulfonamide (30) Following method B with 26 (161 mg, 0.31 mmol, 1.00 eq), 30 (166 mg, 52%) was obtained as a pale white solid. Rf 0.67 (10:90 MeOH/DCM). 1H NMR (500 MHz, CDCl3)) δ 8.286 (s, 1H), 8.292 (s, 1H), 8.14 (s, 1H), 7.82 (s, 1H), 7.66 (d, J = 8.9 Hz, 1H), 6.92 (d, J = 2.6 Hz, 1H), 6.74 (dd, J = 9.0 Hz, J = 2.6 Hz, 1H), 6.01 (d, J = 3.2 Hz, 1H), 5.97–5.88 (m, 5H), 5.31 (dd, J = 6.5 Hz, J = 2.1 Hz, 1H), 4.99 (dd, J = 6.4 Hz, J = 3.7 Hz, 1H), 4.52 (dd, J = 6.1 Hz, J = 4.6 Hz, 1H), 4.43 (dt, J = 8.4 Hz, J = 4.2 Hz, 1H), 4.22 (dd, J = 4.7 Hz, J = 3.2 Hz, 1H), 4.06 (dt, J = 6.1 Hz, J = 3.1 Hz, 1H), 3.97 (dd, J = 11.5 Hz, J = 3.5 Hz, 1H), 3.86–3.49 (m, 10H), 1.55 (s, 3H), 1.33 (s, 3H), 0.90 (br. s, 18H), 0.11–0.05 (m, 12H). 13C NMR (125 MHz, CDCl3) δ 162.8, 155.7, 155.5, 153.2, 152.9, 149.6, 149.1, 149.0, 140.2, 139.7, 133.0, 125.0, 120.4, 120.3, 116.2, 114.7, 109.9, 90.6, 87.4, 84.5, 84.5 (2C), 84.3, 82.6, 82.5, 69.9, 69.6, 61.6, 50.2, 47.2, 27.3, 26.2, 25.9, 25.4, 18.6, 18.2, −4.4, −4.7, −5.3. HRMS (ESI+): m/z calcd for C47H67N12O12SSi2 [M+H]+: 1043.4261, found: 1043.4265.