Reaction Steps
Compound 13c was prepared by the same procedure as described for the preparation of 13a using 4a (415 mg, 1.41 mmol), ethyl chloroacetate (207 mg, 0.18 mL, 1.68 mmol), DIEA (91 mg, 0.12 mL, 0.70 mmol), and DMF (5 mL): yield 204 mg (38%), MS: m/z 381 (M+H)+; 1HNMR (DMSO-d6) δ 8.06 (s, 1H, H-2), 7.11 (bs, 2H, 6-NH2), 5.73 (d, 1H, H-1′, J1′,2′=5.4 Hz), 5.33 (bd, 1H, OH-2′, J2′-2′OH=4.7 Hz), 5.19 (bd, 1H, OH-3′, J3′-3′OH=4.9 Hz), 5.03 (ddd, 1H, H-2′, J1′,2′=5.4 Hz, J2′,3′=5.7 Hz, J2′-2′OH=4.7 Hz), 4.17 (ddd, 1H, H-3′, J2′,3′=5.7 Hz, J3′,4′=4.4 Hz, J3′-3′OH=4.9 Hz), 4.02 (q, 2H, OCH2CH3), 3.92-3.99 (m, 1H, H-4′), 3.27 (bs, 2H, N(CH3)—CH2), 2.83-2.90 (m, 1H, 5′-CH2), 2.70-2.79 (m, 1H, 5′-CH2), 2.53 (s, 3H, 8-CH3), 2.31 (s, 3H, N—CH3), 1.13 (t, 3H, OCH2CH3); UV λmax, nm, pH 1, 258.9 (∈ 16,100), pH 7, 260 (∈ 15,900), pH 13, 260.1 (∈ 16,200). Anal. (C16H24N6O5.0.5CHCl3.0.3CH3OH) C, H, N.
