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Can. J. Chem. Vol. 85, 2007
J1′H,Hβ = 6.6 Hz, J1′H,Hα = 7.9 Hz, 1′H), 5.40 (d, 1H, J =
4.5 Hz, 3′OH), 4.48 (m, 1H, 3H), 3.93 (m, 1H, 4′H), 3.72
(m, 2H, 5′H), 2.53 (m, 1H, 2′Hβ), 2.32 (m, 1H, 2′Hα), 0.98
(s, 9H, t-Bu. 19F-NMR (235.4 MHz, DMSO-d6, ppm) δ –
122.47 (m, 1F, 4F); ESI-MS: 490.2 [M + H]+.
[M + H]+. EI anal. calcd.: C 71.13, H 6.59, N 2.86; found: C
70.84, H 6.83, N 2.67.
General procedure for the preparation of 1-(2′-desoxy-
5′-O-tert-buthyldimethylsisyl-3′-O-mesyl--D-erythro-
pentofuranosyl)-indoles (9a–9f)
To a solution of 1-(2′-desoxy-5′-O-tert-buthyldiphenyl-
silyl-β-D-erythro-pentofuranosyl)-indole (3.2 mmol) in mix-
ture of CH2Cl2 and pyridine (4:1, 75 mL) at 0 °C was added
MsCl (64 mmol) and stirred at RT over night. After the addi-
tion of MeOH (20 mL) and further stirring for 20 min, the
mixture was concentrated to dryness and coevaporated with
toluene. The residue was purified by flash column chroma-
tography (hexane–EtOAc 4:1).
1-(2′-Desoxy-5′-O-tert-buthyldiphenylsilyl--D-erythro-
pentofuranosyl)-6-fluorindole (8b)
This compound was obtained from 7b as a white solid in
1
85% yield. TLC (n-hexan–EtOAc 4:1). Rf 0.20. H NMR
(250 MHz, CDCl3, ppm) δ: 7.65–7.15 (m, 14H, HAr), 6.82
(ddd, 1H, J = 8.7 Hz, J′ = 2.2 Hz, J′′ = 10.1 Hz, 5H), 6.43
(d, 1H, J = 3.2 Hz, 3H), 6.20 (pt, 1H, J1′H,Hβ = 6.3 Hz,
J1′H,Hα = 7.3 Hz 1′H), 5.25 (d, 1H, J = 4.1 Hz, 3′OH), 4.65
(m, 1H, 3H), 3.97 (m, 1H, 4′H), 3.78 (m, 2H, 5′H), 2.57 (m,
1H, 2′Hβ), 2.31 (m, 1H, 2′Hα), 1.02 (s, 9H, t-Bu). 19F NMR
(235.4 MHz, DMSO-d6, ppm) δ: –120.74 (m, 1F, 6F). ESI-
MS: 490.2 [M + H]+.
1-(2′-Desoxy-5′-O-tert-buthyldimethylsisyl-3′-O-mesyl--
D-erythro-pentofuranosyl)-4-fluorindol (9a)
This compound was obtained from 8a as a white foam in
1
90% yield. TLC (hexane–EtOAc 75:25). Rf 0.51. H NMR
(400 MHz, CDCl3, ppm) δ: 7.74–7.12 (m, 13H, HAr), 6.82
(m, 1H, 5H), 6.59 (d, 1H, J = 3.3 Hz, 3H), 6.37 (pt, 1H,
J1′H,2′Hβ = 8.6 Hz, J1′H,2′Hα = 5.5 Hz, 1′H), 5.52 (m, 1H, 3′H),
4.33 (m, 1H, 4′H), 3.88 (m, 2H, 5′H), 3.07 (s, 3H, SCH3),
2.72 (m, 2H, 2′H), 1.12 (s, 9H, t-Bu). 19F NMR:
(235.4 MHz, CDCl3, ppm) δ: –121.87 (m, 1F, 4F). ESI-MS:
568.3 [M + H]+.
1-(2′-Desoxy-5′-O-tert-buthyldiphenylsilyl--D-erythro-
pentofuranosyl)-4,6-fluorindole (8c)
This compound was obtained from 7c as a white solid in
1
88% yield. TLC (n-hexan–EtOAc 1:2). Rf 0.17. H NMR
(400 MHz, DMSO-d6, ppm) δ: 7.56–7.29 (m, 12H, HAr),
6.86 (ddd, 1H, J = 1.9 Hz, J′ = 10.3 Hz, J′′ = 10.2 Hz, 5H),
6.47 (d, 1H, J = 3.4 Hz, 3H), 6.34 (pt, 1H, J1′H,2′Hβ = 6.4Hz,
J
1′H,2′Hα = 6.5 Hz, 1′H), 5.35 (d, 1H, J = 4.6 Hz, 3′OH), 4.43
1-(2′-Desoxy-5′-O-tert-butyldimethylsilyl-3′-O-mesyl--D-
erythro-pentofuranosyl)-6-fluoroindole (9b).
(m, 1H, 3′H), 3.89 (m, 1H, 4′H), 3.72 (m, 2H, 5′H), 2.49 (m,
1H, 2′Hβ), 2.30 (m, 1H, 2′Hα), 2.05 (s, 9H, t-Bu). 13C NMR
(100.6 MHz, DMSO-d6, ppm) δ: 155.7 (d, J = 50.6 Hz, C4),
154.8 (d, J = 62.2 Hz, C6), 141.5 (C8), 137.5 (CAr), 135.8
(CAr), 135.6 (CAr), 135.2 (CAr), 133.0 (CAr), 132.2 (CAr),
129.8 (CAr), 128.5 (CAr), 128.2 (CAr), 128.1 (CAr), 127.9
(CAr), 127.5 (CAr), 126.9 (C2), 111.2 (C9), 103.1 (C3), 95.7
(C5), 93.6 (C7), 83.5 (C1′), 83.3 (C4′), 65.3 (C3′), 64.2 (C5′),
36.0 (C2′), 25.73 (SiC(CH3)3), 20.5 (SiC(CH3)3). 19.5
(SiC(CH3)3), 14.5 (SiC(CH3)3). ESI-MS: 505.8 [M – H]–.
This compound was obtained from 8b as a white foam in
1
97% yield. TLC (hexane–EtOAc 4:1). Rf 0.30. H NMR
(400 MHz, DMSO-d6, ppm) δ: 7.69–7.20 (m, 14H, HAr),
6.93 (ddd, 1H, J = 8.8 Hz, J′ = 2.3 Hz, J′′ = 9.4 Hz, 5H),
6.32 (pt, 1H, J1′H,2′Hβ = 5.5 Hz, J1′H,2′Hα = 3.5 Hz, 1′H), 5.53
(m, 1H, 3′H), 4.34 (m, 1H, 4′H), 3.93 (dd, 1H, J = 11.4 Hz,
J′ = 3.2 Hz, 5′Hα), 3.84 (dd, 1H, J = 4.2 Hz, J′ = 11.4 Hz,
5′Hβ), 3.10 (s, 3H, SCH3), 2.76 (m, 1H, 2′Hβ), 2.47 (m, 1H,
2′Hα), 1.14 (s, 9H, t-Bu). 13C NMR (100.6 MHz, DMSO-d6,
ppm) δ: 161.18 (CAr), 158.81 (C4), 136.42 (CAr), 135.58 (d,
J = 10.6 Hz, C6), 132.48 (CAr), 129.97 (C8), 127.92 (CAr),
125.44 (C3), 124.38 (CAr), 121.69 (C9), 109.25 (C7), 96.75
(C2), 96.45 (C5), 84.87 (C1′), 83.90 (C3′), 80.27 (C4′),
76.68 (C5′), 63.38 (C2′), 38.44 (SCH3), 26.92 (SiC(CH3)3),
19.24 (SiC(CH3)3). ESI-MS: 568.5 [M + H]+.
1-(2′-Desoxy-5′-O-tert-buthyldiphenylsilyl--D-erythro-
pentofuranosyl)-5-fluorindole (8d)
This compound was obtained from 7d as a white solid in
1
86% yield. TLC (n-hexan–EtOAc 4:1). Rf 0.23. H NMR
(400 MHz, DMSO-d6, ppm) δ: 8.62 (d, 1H, J = 3.1 Hz, 2H),
7.50 (m, 12H, HAr), 6.95 (ddd, 1H, J = 8.6 Hz, J′ = 2.1 Hz,
J′′ = 10.1 Hz, 6H), 6.45 (m, 2H, 2H, 1′H), 5.44 (d, 1H, J =
4.2 Hz, 3′OH), 4.53 (m, 1H, 3′H), 4.05 (m, 1H, 4′H), 3.85
(m, 2H, 5′H), 2.60 (m, 1H, 2′Hβ), 2.38 (m, 1H, 2′Hα), 1,04
(s, 9H, t-Bu). 19F NMR (283.3 MHz, DMSO-d6, ppm) δ:
–124.76 (m, 1F, 5F) ESI-MS: 489.1 [M – H]–.
1-(2′-Desoxy-5′-O-tert-buthyldimethylsisyl-3′-O-mesyl--
D-erythro-pentofuranosyl)-4,6-fluorindole (9c)
This compound was obtained from 8c as a white foam in
1
99% yield. TLC (n-hexan–EtOAc 85:15). Rf 0.16. H NMR
(400 MHz, DMSO-d6, ppm) δ: 7.60–7.33 (m, 12H, HAr),
6.92 (m, 1H, 5H), 6.54 (d, 1H, J = 3.4 Hz, 3H), 6.45 (pt, 1H,
J1′H,2′Hβ = 6.3 Hz, J1′H,2′Hα = 6.4 Hz, 1′H), 5.44 (m, 1H, 3′H),
4.26 (m, 1H, 4′H), 3.81 (m, 2H, 5′H), 3.30 (s, 9H, SCH3),
2.85 (m, 1H, 2′Hβ), 2.73 (m, 1H, 2′Hα), 0.99 (s, 9H, t-Bu).
19F NMR (235.3 MHz, DMSO-d6, ppm) δ: –119.02 (m, 1F,
6F), –117.84 (m, 1F, 4F). ESI-MS: 505.8 [M + H]+. EI anal.
calcd.: C 61.52, H 5.68, N 2.39; found: C 61.35, H 5.47, N 2.43.
1-(2′-Desoxy-5′-O-tert-buthyldiphenylsilyl--D-erythro-
pentofuranosyl)-7-fluorindole (8e)
This compound was obtained from 7e as a white solid in
1
89% yield. TCL (n-hexan–EtOAc 4:1). Rf 0.36. H NMR
(400 MHz, DMSO-d6, ppm) δ: 7.66 (m, 5H, HAr), 7.48–7.38
(m, 7H, HAr), 7.10–7.01 (m, 2H, HAr), 6.60 (pt, 1H, J1′H,Hβ
=
6.3 Hz, J1′H,Hα = 7.1 Hz, 1′H), 6.55 (d, 1H, J = 3.1 Hz, 2H),
5.47 (d, 1H, J = 4.3 Hz, 3′OH), 4.50 (m, 1H, 3′H), 3.97 (m,
1H, 4′H), 3.77 (m, 2H, 5′H), 2.48 (m, 1H, 2′Hβ), 2.39 (m,
1H, 2′Hα), 1.04 (s, 9H, t-Bu). 19F NMR (282.3 MHz,
DMSO-d6, ppm) δ: –132.64 (m, 1F, 7F). ESI-MS: 490.2
1-(2′-Desoxy-5′-O-tert-buthyldimethylsisyl-3′-O-mesyl--
D-erythro-pentofuranosyl)-5-fluorindole (9d)
This compound was obtained from 8d as a white foam in
89% yield. Yield 2.89 g (89%). TLC (n-hexan–EtOAc 4:1).
© 2007 NRC Canada