Following method A with 5′-amino-2′,3′-isopropylidene adenosine (280 mg, 0.92 mmol, 1.00 eq) and 4-methoxy-2-nitrobenzenesufonyl chloride, 26 (191 mg, 40%) was obtained as a beige solid. Rf 0.59 (8:92 MeOH/DCM). 1H NMR (600 MHz, DMSO‑d 6) δ 8.43 (t, J = 5.8 Hz, 1H), 8.28 (s, 1H), 8.12 (s, 1H), 7.74 (d, J = 8.9 Hz, 1H), 7.51 (d, J = 2.6 Hz, 1H), 7.40 (br. s, 2H), 7.20 (dd, J = 8.9 Hz, J = 2.6 Hz, 1H), 6.11 (d, J = 3.0 Hz, 1H), 5.36 (dd, J = 6.3 Hz, J = 3.0 Hz, 1H), 4.93 (dd, J = 6.4 Hz, J = 2.9 Hz, 1H), 4.23 (td, J = 5.8 Hz, J = 2.9 Hz, 1H), 3.87 (s, 3H), 3.27–3.14 (m, 2H), 1.52 (s, 3H), 1.28 (s, 3H). 13C NMR (150 MHz, DMSO‑d 6) δ 162.5, 156.2, 153.0, 149.0, 148.3, 140.2, 131.3, 123.8, 119.3, 117.2, 113.5, 109.8, 89.5, 84.1, 82.8, 81.5, 56.6, 44.5, 27.0, 25.1. HRMS (ESI+): m/z calcd for C20H24N7O8S [M+H]+: 522.1407, Found 522.1407.