816
Bobkov, Brilliantov, Mikhailov, Rozenski, Van Aerschot, Herdewijn:
5.9 (OH-3′); 5.31 dd, 1 H, J(5,NH) = 2.2 (H-5); 4.79 d, 1 H, J = –7.2 (OCHHO); 4.77 d, 1 H
(OCHHO); 4.27–4.24 m , 2 H (H-2′, H-3′); 4.12–3.97 m , 2 H (OCH2CH2OAc); 4.09 m , 1 H
(H-4′); 3.74 s, 3 H (OMe); 3.69 m , 2 H (OCH2CH2OAc); 3.29 dd, 1 H, J(5′a,4′) = 4.4, J(5′a,5′b) =
–10.5 (H-5′a); 3.21 dd, 1 H, J(5′b,4′) = 2.2 (H-5′b); 1.97 s, 1 H (Ac). 13C NMR (DMSO-d6):
170.17 (C=O); 162.76 (C-4); 158.22 (Ph OMe); 150.26 (C-2); 143.79, 143.53 (Ph ); 140.36
(C-6); 134.35, 129.87, 127.71, 127.70, 126.97 (Ph ); 113.31 (Ph OMe); 101.32 (C5); 94.10
(OCH2O); 87.13 (C-1′); 86.10 (Ph 3C); 82.90 (C-4′); 77.43 (C-2′); 68.38 (C-3′); 65.18
(OCH2CH2OAc); 63.09 (OCH2CH2OAc); 61.58 (C-5′); 54.87 (OMe); 20.59 (Me, Ac).
1-{2-O-[(2-Acetoxyeth oxy)m eth yl]-5-O-(4-m eth oxytrityl)-β-D-ribofuran osyl}-
N4-ben zoylcytosin e (10b)
An alogous tritylation of n ucleoside 6b (463 m g, 1 m m ol) yielded 10b as a foam (589 m g,
80%). RF 0.33 (A). 1H NMR (DMSO-d6): 11.24 brs, 1 H (NH); 8.32 d, 1 H, J(6,5) = 7.5 (H-6);
8.02–7.28 m , 17 H (Bz, Tr); 7.16 brd, 1 H (H-5); 6.94 d, 2 H, J = 8.1 (Ph OMe); 5.89 d, 1 H,
J(1′,2′) = 1.6 (H-1′); 5.35 brs, 1 H (OH); 4.97 d, 1 H, J = –6.7 (OCHHO); 4.87 d, 1 H
(OCHHO); 4.36 dd, 1 H, J(3′,2′) = 5.0, J(3′,4′) = 8.1 (H-3′); 4.21 dd, 1 H (H-2′); 4.15 t, 2 H, J =
4.7 (OCH2CH2OAc); 4.09 ddd, 1 H, J(4′,5a′) = 3.4, J(4′,5b′) = 2.7 (H-4′); 3.79 m , 2 H
(OCH2CH2OAc); 3.76 s, 3 H (OMe); 3.42 dd, 1 H, J(5′a,5′b) = –11.2 (H-5′a); 3.35 dd, 1 H
(H-5′b); 1.99 s, 3 H (Ac). 13C NMR (DMSO-d6): 170.24 (C=O, Ac); 167.65 (C=O, Bz); 163.11
(C-4); 158.27 (Ph OMe); 154.73 (C-2); 144.43 (C-6); 143.96, 143.68, 134.83, 132.65, 129.94,
128.37, 128.09, 127.79 (Ph ); 113.30 (Ph OMe); 96.12 (C-5); 93.69 (OCH2O); 89.30 (C-1′);
86.26 (Ph 3C); 82.02 (C-4′); 78.31 (C-2′); 67.86 (C-3′); 65.20 (OCH2OCH2CH2OAc); 63.09
(OCH2OCH2CH2OAc); 61.85 (C-5′); 54.98 (OMe); 20.57 (Me, Ac).
1-{2-O-[(3-Acetoxypropoxy)m eth yl]-5-O-(4-m eth oxytrityl)-β-D-ribofuran osyl}uracil (11a)
An alogous tritylation of n ucleoside 7a (375 m g, 1 m m ol) yielded 11a as a foam (498 m g,
77%). RF 0.33 (A). 1H NMR (CDCl3): 8.47 brs, 1 H (NH); 7.94 d, 1 H, J(6,5) = 8.1 (H-6);
7.52–7.34 m , 12 H (Ph ); 6.86 d, 2 H, J = 8.7 (Ph OMe); 5.99 d, 1 H, J(1′,2′) = 2.8 (H-1′); 5.31 dd,
1 H, J(5,NH) = 1.9 (H-5); 4.98 d, 1 H, J = –6.7 (OCHHO); 4.87 d, 1 H (OCHHO); 4.48 dt, 1 H,
J(3′,2′) = 5.6, J(3′,OH) = 7.5, J(3′,4′) = 5.6 (H-3′); 4.29 dd, 1
H (H-2′); 4.16 m , 2 H
(OCH2CH2CH2OAc); 4.05 dt, 1 H, J(4′,5a′) = 2.2, J(4′,5b′) = 2.2 (H-4′); 3.80 s, 3 H (OMe);
3.72 m , 1 H (OCHHCH2CH2OAc); 3.62 m , 1 H (OCHHCH2CH2OAc); 3.54 d, 2 H (H-5′a,
H-5′b); 2.72 d, 1 H (OH-3′); 2.04 d, 3 H (Ac); 1.92 p, 2 H, J = 6.2 (OCH2CH2CH2OAc). 13C NMR
(DMSO-d6): 170.17 (C=O); 162.76 (C-4); 158.22 (Ph OMe); 150.26 (C-2); 143.99, 143.73 (Ph );
140.11 (C-6); 134.55, 129.97, 127.91, 127.80, 126.87 (Ph ); 113.21 (Ph OMe); 101.52 (C-5);
94.00 (OCH2O); 87.03 (C-1′); 86.20 (Ph 3C); 82.80 (C-4′); 77.53 (C-2′); 68.58 (C-3′); 64.18
(OCH2CH2CH2OAc); 62.88 (C-5′); 60.98 (OCH2CH2CH2OAc); 54.97 (OMe); 28.40
(OCH2CH2CH2OAc); 20.49 (Me, Ac).
1-{2-O-[(3-Acetoxypropoxy)m eth yl]-5-O-(4-m eth oxytrityl)-β-D-ribofuran osyl}-
N4-ben zoylcytosin e (11b)
An alogous tritylation of n ucleoside 7b (477 m g, 1 m m ol) yielded 11b as a foam (578 m g,
77%). RF 0.33 (A). 1H NMR (DMSO-d6): 11.23 brs, 1 H (NH); 8.33 d, 1 H, J(6,5) = 7.6 (H-6);
8.02–7.28 m , 17 H (Bz, Tr); 7.15 brd, 1 H (H-5); 6.93 d, 2 H, J = 9.0 (Ph OMe); 5.90 s, 1 H
(H-1′); 5.32 brs, 1 H (OH-3′); 4.93 d, 1 H, J = –6.5 (OCHHO); 4.83 d, 1 H (OCHHO); 4.35 dd,
Collect. Czech. Chem. Commun. 2006, Vol. 71, No. 6, pp. 804–819