3ꢁ-Acetamidoadenosine Derivatives
419
J = 1.1 Hz), 5.92 (s, 1H), 5.12∼5.06 (m, 1H), 4.85∼4.80 (dd, 1H, J = 2.9
and 12.3 Hz), 4.68∼4.54 (m, 3H), 3.73 (s, 3H), 2.13 (m, 2H), 1.77∼1.69 (m,
4H), 1.56∼1.52 (m, 2H); IR (neat) 3355, 2955, 1726 cm−1; MS (FAB) m/z
621 (M+H); Anal. Calcd for C31H30ClN5O7: C, 60.05; H, 4.88; N, 11.29.
Found: C, 60.36; H, 5.01; N, 10.85. A solution of protected nucleoside (128
mg, 0.206 mmol) in 40% MeNH2 : THF(1:1, 4 mL) was stirred at room
temperature for 3 hours. Solvents were removed under reduced pressure
and the residue purified by prep. TLC (methylene chloride : methanol =
20:1, twice) to give 3e (19 mg, 22%): mp 245.0∼245.6◦C; UV (MeOH) λmax
273 nm (pH 7); [α]25 −17.66◦ (c 0.8, THF); 1H NMR (CD3OD, 400 MHz)
D
δ 8.34 (s, 1H), 5.99 (d, 1H, J = 2.7 Hz), 4.80∼4.79 (m, 1H), 4.63∼4.62 (m,
1H), 4.50 (s, 1H), 3.99∼3.96 (dd, 1H, J = 1.6 and 10.0 Hz), 3.70∼3.67 (dd,
1H, J = 1.9, 2.0 and 10.0 Hz), 3.32 (s, 1H), 2.75 (s, 3H), 2.10∼2.00 (m, 2H),
1.79 (m, 2H), 1.76∼1.67 (m, 2H), 1.63∼1.58 (m, 2H); IR (neat) 3430, 2955,
1640 cm−1; MS (FAB) m/z 411 (M+H); Anal. Calcd for C17H23ClN6O4: C,
49.70; H, 5.64; N, 20.45. Found: C, 49.56; H, 5.92; N, 20.71.
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