482
Kamaike, Namiki, and Kawashima
1
as described above. H-NMR (CDCl3) d 1.20–1.25 (m, 6H, CH(CH3)2, 1.34 (t, 9H,
J ¼ 7.3 Hz, CH2CH3 ꢁ 3), 2.16 (s, 3H, COCH3), 2.50–2.53 (m, 3H, H-20 and
OCOCH2CH2COCH3), 2.69–2.74 (m, 4H, OCOCH2CH2COCH3, CH(CH3)2, and
H-200), 3.08 (q, 6H, J ¼ 7.3 Hz, CH2CH3 ꢁ 3), 3.94 (s, 3H, OCH3), 4.25–4.27 (m,
1H, H-40), 4.40–4.43 (m, 1H, H-50), 4.61–4.64(m, 1H, H-5’’), 4.70 (s, 2H, PhCH2),
6.04–6.10 (m, 2H, H-10 and 30), 7.00 (d, 1H, JP,H ¼ 626.4 Hz, P-H), 7.16 (d, 1H,
J ¼ 8.8 Hz, Ph-H of LMMoNBz group), 7.51 (d, 1H, J ¼ 8.8 Hz, Ph-H of LMMoNBz
group), 7.64 (s, 1H, H-8), 10.99 (br s, 1H, N1-H), and 11.65 (br s, 1H, N2-H).
31P-NMR (CDCl3) d 4.23.
50-O-[2-(Levulinyloxymethyl)-5-methoxy-4-nitrobenzoyl]thymidine 30-H-phospho-
nate triethylammonium salt [10a ( p)]. Compound 10a ( p) was obtained in 91% yield
(0.319 g) as a colorless foam by treating 9a (p) (0.274 g, 0.5 mmol) with tris(1,2,4-tri-
azolyl)phosphine (2.5 mmol) and a subsequent work-up as described above. 1H-NMR
(CDCl3) d 1.36 (t, 9H, J ¼ 7.3 Hz, CH2CH3 ꢁ 3), 1.84 (s, 3H, CH3 of thymidine), 2.20
(s, 3H, COCH3), 2.28–2.32 (m, 1H, H-20), 2.58–2.62 (m, 1H, H-200), 2.66 (t, 2H,
J ¼ 6.4 Hz, OCOCH2CH2COCH3), 2.80 (t, 2H, J ¼ 6.4 Hz, OCOCH2CH2COCH3),
3.09 (q, 6H, J ¼ 7.3 Hz, CH2CH3 ꢁ 3), 4.03 (s, 3H, OCH3), 4.43–4.46 (m, 1H, H-40),
4.63–4.68 (m, 2H, H-50 and 500), 4.89–4.92 (m, 1H, H-30), 5.42, 5.47 (2d, 2H,
0
0
0
0
00
J ¼ 14.4 Hz, PhCH2), 6.30 (t, 1H, J1 ,2 ¼ J1 ,2 ¼ 6.7 Hz, H-1 ), 6.96 (d, 1H, JP,H
¼
620.6 Hz, P-H), 7.18 (s, 1H, H-6), 7.73 (s, 1H, Ph-H), 7.96 (s,1H, Ph-H), and
8.63 (br s, 1H, N3-H). 31P-NMR (CDCl3) d 4.07.
N 4-Anisoyl-50-O-[2-(levulinyloxymethyl)-5-methoxy-4-nitrobenzoyl]-20-deoxy-
cytidine 30-H-phosphonate triethylammonium salt [10b ( p)]. Compound 10b (p) was
obtained in 86% yield (0.360 g) as a colorless foam by treating 9b (p) (0.344 g,
0.5 mmol) with tris(1,2,4-triazolyl)phosphine (2.5 mmol) and a subsequent work-
1
up as described above. H-NMR (CDCl3) d 1.34 (t, 9H, J ¼ 7.3 Hz, CH2CH3 ꢁ
3), 2.17 (s, 3H, COCH3), 2.24–2.27 (m, 1H, H-20), 2.64 (t, 2H, J ¼ 6.4 Hz,
OCOCH2CH2COCH3), 2.78 (t, 2H, J ¼ 6.4 Hz, OCOCH2CH2COCH3), 3.02–3.08
(m, 1H, H-200), 3.05 (q, 6H, J ¼ 7.3 Hz, CH2CH3 ꢁ 3), 3.88 (s, 3H, OCH3 of
An group), 4.00 (s, 3H, OCH3 of LMMpNBz group), 4.60–4.65 (m, 1H, H-40),
4.67–4.69 (m, 2H, H-50 and 500), 4.69–4.70 (m, 1H, H-30), 5.39, 5.46 (2d, 2H, J ¼
0
0
0
0
00
14.2 Hz, PhCH2), 6.24 (t, 1H, J1 ,2 ¼ J1 ,2 ¼ 6.2 Hz, H-1 ), 6.93 (d, 1H, JP,H
¼
620.4 Hz, P-H), 6.98 (d, 2H, J ¼ 8.8 Hz, Ph-H ꢁ 2 of An group), 7.40–7.49 (m, 1H,
H-5), 7.67 (s, 1H, Ph-H of LMMpNBz group), 7.85 (d, 2H, J ¼ 8.8 Hz, Ph-H ꢁ 2
of An group), 7.93 (s,1H, Ph-H of LMMpNBz group), and 7.94–7.98 (m, 1H, H-6).
31P-NMR (CDCl3) d 4.05.
N6-Benzoyl-50-O-[2-(levulinyloxymethyl)-5-methoxy-4-nitrobenzoyl]-20-deoxyade-
nosine 30-H-phosphonate triethylammonium salt [10c ( p)]. Compound 10c (p) was
obtained in 86% yield (0.357 g) as a colorless foam by treating 9c (p) (0.331 g,
0.5 mmol) with tris(1,2,4-triazolyl)phosphine (2.5 mmol) and a subsequent work-up
as described above. 1H-NMR (CDCl3) d 1.31 (t, 9H, J ¼ 7.3 Hz, CH2CH3 ꢁ 3),
2.16 (s, 3H, COCH3), 2.62 (t, 2H, J ¼ 6.3 Hz, OCOCH2CH2COCH3), 2.75 (t, 2H,
J ¼ 6.3 Hz, OCOCH2CH2COCH3), 2.78–2.83 (m, 1H, H-20), 3.00 (q, 6H, J ¼ 7.3 Hz,
Hz, CH2CH3 ꢁ 3), 3.10–3.13 (m, 1H, H-200), 3.97 (s, 3H, OCH3), 4.58–4.61 (m, 1H,