ORDER
REPRINTS
[(b-D-Ribofuranosyloxy)methyl]nucleosides
663
2.24 mmol) in CHCl3 (40 mL) at reflux for 3 h to isoltate the title compound as a pale
yellow solid (1.07 g, 98.1% yield). mp 78–80°C; [a]D 16.0 (c 1.0, CHCl3); UV lmax
(MeCN) nm: 259; IR (KBr) nmax 3062, 2107, 1723, 1677, 1446, 1262, 1154, 1086,
1015, 816 and 692 cmÀ1; 1H NMR (200 MHz; CDCl3) d 4.60 (1H, dd, J = 13.0, 5.5 Hz,
H5’), 4.60–4.80 (2H, m, H4’,H5@), 5.14, 5.38 (2H, AB type quartet, J = 10.0 Hz,
OCH2N), 5.50 (1H, s, H1’), 5.62 (1H, d, J = 5.6 Hz, H2’), 5.65 (1H, d, J = 5.5 Hz, H5),
5.82 (1H, dd, J = 4.0 Hz, H3’), 7.18 (1H, d, H6), 7.20–8.20 (15H, m, aromatic), 9.0
(1H, br s, NH); 13C NMR (50 MHz; CDCl3) d 64.3 (C5’), 71.7 (C4’), 74.5 (C3’), 75.5
(C2’), 78.0 (OCH2N), 103.0 (C5), 104.5 (C1’), 127–135 (aromatic), 143.5 (C6), 150.0
(C=O, C2), 163.5 (C=O, C4), 165.0, 165.3 and 166.0 (C=O, ester); FAB-MS m/z: 609
[M+ + Na]; Anal calcd for C31H26O10N2:C, 63.48; H, 4.47; N, 4.78 Found: C, 63.37; H,
4.36; N, 4.67.
1-[(2,3,5-Tri-O-benzoyl-b-D-ribofuranosyloxy)methyl]thymine (6b). Prepared
according to method B (2.22 mmol) by reacting 4 (1.0 g, 1.87 mmol) and 5b (0.6 g,
2.22 mmol) in CHCl3 (40 mL) at reflux for 4 h to isoltate the title compound as a white
crystalline solid (0.88 g, 78.6% yield). mp 82-84°C; [a]D 41.0 (c 1.0, CHCl3); UV lmax
(MeOH) nm: 266; IR (KBr) nmax 3176, 2970, 1721, 1684, 1369, 1307, 1269, 1092,
1
1062 and 1031 cmÀ1; H NMR (200 MHz; CDCl3) d 1.90 (3H, s, CH3), 4.50 (1H, dd,
J = 14.0, 6.5 Hz, H5’), 4.60–4.80 (2H, m, H4’,H5@), 5.10,5.36 (2H, AB type quartet,
J = 10.0 Hz, OCH2N), 5.50 (1H, s, H1’), 5.70 (1H, d, J = 5.0 Hz, H2’), 5.80 (1H, dd,
J = 4.0 Hz, H3’), 6.98 (1H, s, H6), 7.20–8.20 (15H, m, aromatic), 8.50 (1H, br s, NH);
13C NMR (50 MHz; CDCl3) d 12.2 (CH3), 64.6 (C5’), 74.5 (C4’), 76.0 (C3’), 78.0
(C2’), 80.0 (OCH2N), 104.7 (C1’), 111.5 (C5), 127–135 (aromatic), 151.0 (C=O,C2)
164.0 (C=O,C4) 164.8, 165.0 and 165.8 (C=O,ester); FAB-MS m/z: 601 [M+ + H];
Anal. cacld for C32H28O18N2:C, 63.99; H, 4.70; N, 4.66. Found: C, 64.17; H,
4.62; N, 4.59.
1-[(2,3,5-Tri-O-benzoyl-b-D-ribofuranosyloxy)methyl]cytosine (6c). Prepared
according to method A (6.74 mmol) by reacting 4 (3.0 g, 5.61 mmol) and 5a (1.71
g, 6.74 mmol) in CHCl3 (30 mL) at room temperature for 6 h to isolate after
chromatographic separation (ethyl acetate:chloroform, 2:1) 7c (1.47 g, 47.4% yield)) as
a crystalline solid mp 180–82°C (lit.13 mp 182–83°C) and the title compound 6c (0.96 g,
29.5% yield) as a white crystalline solid. mp 178–181°C; [a]D 29.0 (c 1.0, CHCl3);
UV lmax (MeOH) nm: 271; IR (KBr) nmax 3336, 3200, 1728, 1664, 1616, 1488, 1370,
1
1264, 1088 and 1040 cmÀ1; H NMR (200 MHz; CDCl3) d 4.50 (1H, dd, J = 13.0,
J = 5.0 Hz, H5’), 4.60–4.80 (2H, m, H4’,H5@), 5.15, 5.40 (2H, AB type quartet,
J = 10.0 Hz, OCH2N), 5.60 (1H, s, H1’), 5.70 (d, J = 5.0 Hz, H2’), 5.85 (1H,dd,
J = 3.0 Hz, H3’), 5.95 (1H,d, J = 7.5 Hz, H5), 7.15–8.15 (16H, m, H6, aromatic); 13C
NMR (50 MHz; CDCl3) d 64.7 (C5’), 72.1 (C4’), 75.5 (C2’), 76.5 (C3’), 79.5 (OCH2N),
104.2 (C1’), 128–135 (aromatic), 144.6 (C6), 156.1 (C4), 165.1 (C=O,C2) 165.4,
166.0, 166.1 (C=O,ester); FAB-MS m/z: 586 [M+ + H]; Anal. cald for C31H27O9N3: C,
63.58; H, 4.65; N, 7.18. Found: C, 63.41; H, 4.59; N, 7.12.
N4Benzoyl-1-[(2,3,5-tri-O-benzoyl-b-D-ribofuranosyloxy)methyl]cytosine (6d).
Prepared according to method B (1.11 mmol) by reacting 4 (0.5 g, 0.93 mmol) and
5d (0.4 g, 1.11 mmol) in CHCl3 (20 mL) at reflux temperature for 4 h to isoltate after