6830
B. Gerland et al. / Bioorg. Med. Chem. 16 (2008) 6824–6831
(3H, m, CH2–CH3); 13C NMR (100 MHz, CDCl3) d 163.3 (C2), 150.0
(C4), 136.5 (C6), 110.8 (C5), 85.8 (C10), 85.4 (C40), 61.5 (50-CH2),
45.2 (C30), 39.8 (CH2–S), 38.2 (20-CH2), 31.2 (S–CH2–CH2), 21.5
(CH2–CH3), 13.6 (CH2–CH3), 12.5 (5-CH3); MS (FAB+, NBA) m/z
347 [M+H]+, 369 [M+Na]+; HRMS for C14H22N2O4NaS2 [M+Na]+, cal-
culated 369.0919, found 369.0918. The nucleoside symmetrical
disulfide 5 formed under these conditions was isolated (23%).
Compound 18 was also obtained directly from TMSE sulfide 13.
To a stirred solution of 13 (40 mg, 0.112 mmol) in dichloromethane
m
/z 335 [M+H]+; HRMS for C12H18N2O5NaS2, [M+Na]+, calculated
357.0555, found 357.0549. The nucleoside symmetrical disulfide
5 formed under these conditions was isolated (24%).
4.1.14. 20,30-Dideoxy-30-(2-aminoethyldithio)thymidine (22)
Compound 22 (9 mg, 0.024 mmol, 20%) was obtained as a white
powder from 16 (50 mg, 0.12 mmol), 2-aminoethanethiol hydro-
chloride (28 mg, 0.24 mmol), imidazole buffer (1 M, pH 6.0,
400 lL), and a mixture of THF/imidazole buffer (2.0/2.0 mL),
15 h; 1H NMR (400 MHz, D2O) d 7.54 (1H, s, 6-H), 6.08 (1H, dd,
J = 4.4 Hz, J = 7.2 Hz, 10-H), 4.02 (1H, m, 40-H), 3.87 (1H, dd,
J = 2.8 Hz, J = 12.8 Hz, 50-H), 3.76 (1H, dd, J = 2.8 Hz, J = 12.8 Hz,
50-H), 3.52 (1H, m, 30-H), 3.30 (2H, m, CH2–NH2), 2.93 (2H, m,
CH2–S), 2.60–2.43 (2H, m, 20-H ꢁ 2), 1.80 (3H, s, 5-CH3); 13C NMR
(100 MHz, D2O) d 166.4 (C2), 151.5 (C4), 137.5 (C6), 111.1 (C5),
85.1 (C40), 84.8 (C10), 60.5 (50-CH2), 45.1 (C30), 37.8 (CH2–NH2),
36.9 (20-CH2), 35.0 (CH2–S), 11.5 (5-CH3); MS (DCI, NH3-isobutane)
m/z 334 [M+H]+; HRMS for C12H20N3O4NaS2, [M+Na]+, calculated
356.0715, found 356.0721. The nucleoside symmetrical disulfide
5 formed under these conditions was isolated (48%).
were added successively dibutyl disulfide (106 lL, 0.56 mmol) and
a solution of Br2 in dichloromethane (1 M, 1.12 mmol). The result-
ing solution was stirred under argon at rt overnight, then an aque-
ous solution of sodium thiosulfate (5%, 2 mL) was added. The
organic phase was washed with water (10 mL), dried over MgSO4,
and evaporated. Methanol was added to precipitate 18 (10 mg,
0.029 mmol, 26%). The non-precipitated fraction was evaporated
to give the symmetrical disulfide 5 (10 mg, 0.019 mmol, 33%).
4.1.11. 20,30-Dideoxy-30-(hexyldithio)thymidine (19)
Compound 19 (22 mg, 0.059 mmol, 71%) was obtained as a
white powder from 16 (34 mg, 0.083 mmol), hexanethiol (123
lL,
0.83 mmol), THF (6 mL) and phosphate buffer (243 L), 2 h; mp
l
4.1.15. 20,30-Dideoxy-30-(6-hydroxyhexyldithio)thymidine (23)
Compound 23 (37 mg, 0.094 mmol, 73%) was obtained as a
white powder from 16 (55 mg, 0.13 mmol), 6-mercaptohexanol
64–66 °C (decomposition); 1H NMR (400 MHz, CDCl3) d 8.66 (1H,
s, NH), 7.56 (1H, s, 6-H), 6.12 (1H, dd, J = 4.7 Hz, J = 7.2 Hz, 10-H),
4.10–4.01 (2H, m, 40-H, 50-H), 3.90 (1H, m, 50-H), 3.60 (1H, m, 30-
H), 2.70 (2H, m, CH2–S), 2.64–2.48 (2H, m, 20-H ꢁ 2), 1.92 (3H, s,
5-CH3), 1.68 (2H, m, CH2–CH2–S), 1.44–1.25 (6H, m, CH2–CH2–
CH2), 0.91 (3H, m, CH2–CH3); 13C NMR (100 MHz, CDCl3) d 163.4
(C2); 150.1 (C4), 133.4 (C6), 110.8 (C5), 85.8 (C10), 85.5 (C40),
61.5 (50-CH2), 45.3 (C30), 40.2 (CH2–S), 38.2 (20-CH2), 31.3 (CH2),
29.1 (CH2–CH2–S), 28.0, 22.4 (2 CH2), 13.9 (CH2–CH3), 12.4 (5-
CH3); MS (DCI, NH3-isobutane) m/z 375 [M+H]+; elemental analysis
for C16H26N2O4S2, calculated C 51.31, H 7.00, N 7.48, found C 51.26,
H 6.70, N 7.57; HRMS for C16H26N2O4NaS2 [M+Na]+, calculated
397.1232, found 397.1230.
(183 lL, 1.34 mmol), phosphate buffer (5%, pH 9.5, 334 lL), and
THF (6 mL), 2 h; mp 106–108 °C; 1H NMR (400 MHz, CD3OD) d
7.94 (1H, s, 6-H), 6.16 (1H, dd, J = 4.8 Hz, J = 6.8 Hz, 10-H), 4.02–
3.92 (2H, m, 40-H, 50-H), 3.81 (1H, m, 50-H), 3.58 (3H, m, 30-
H + CH2-OH), 2.79 (2H, m, CH2–S), 2.62–2.42 (2H, m, 20H ꢁ 2),
1.90 (3H, s, 5-CH3), 1.74 (2H, m, CH2–CH2–S), 1.56 (2H, m, CH2–
CH2-OH), 1.44 (4H, m, CH2–CH2); 13C NMR (100 MHz, CD3OD) d
162.2 (C2), 150.8 (C4), 136.8 (C6), 109.8 (C5), 85.6 (C40), 84.5
(C10), 61.4 (CH2–OH), 60.6 (50-CH2), 45.4 (C30), 39.2 (CH2–S), 38.0
(20-CH2), 32.0 (CH2–CH2–OH), 28.7 (CH2–CH2–S), 27.8, 25.0 (2
CH2), 11.0 (5-CH3); MS (DCI, NH3-isobutane) m/z 391 [M+H]+; ele-
mental analysis for C16H26N2O5S2, calculated C 49.21, H 6.71, N
7.17, S 16.42, found C 49.29, H 6.99, N 7.06, S 16.69; HRMS for
4.1.12. 20,30-Dideoxy-30-(octyldithio)thymidine (20)
Compound 20 (12 mg, 0.030 mmol, 16%) was obtained as a
white powder from 16 (75 mg, 0.18 mmol), octanethiol (316 lL,
C
16H26N2O5NaS2 [M+Na]+, calculated 413.1181, found 413.1193.
1.82 mmol), a mixture of THF/imidazole buffer (2.5/2.5 mL) and
imidazole buffer (10ꢀ3 M, pH 6.0, 5 mL), 15 h; 1H NMR (400 MHz,
CDCl3) d 8.66 (1H, s, NH), 7.68 (1H, s, 6-H), 6.13 (1H, dd,
J = 4.4 Hz, J = 6.8 Hz, 10-H), 4.09–3.88 (3H, m, 40-H, 50-H ꢁ 2), 3.60
(1H, m, 30-H), 2.73 (2H, m, CH2–S), 2.74–2.51 (2H, m, 20-H ꢁ 2),
1.93 (3H, s, 5-CH3), 1.68 (2H, m, CH2–CH2–S), 1.39–1.20 (10H, m,
CH2–CH2–CH2–CH2–CH2), 0.90 (3H, m, CH2–CH3); 13C NMR
(100 MHz, CDCl3) d 163.5 (C2), 150.1 (C4), 136.5 (C6), 110.8 (C5),
85.8 (C10), 85.4 (C40), 61.4 (50-CH2), 45.2 (C30), 40.1 (CH2–S), 38.1
(20-CH2), 31.7 (CH2), 29.2 (CH2–CH2–S), 29.1, 28.4, 22.6 (4 CH2),
14.0 (CH2–CH3), 12.5 (5-CH3); MS (DCI, NH3-isobutane) m/z 403
[M+H]+; HRMS for C18H30N2O4NaS2 [M+Na]+, calculated 425.1545,
found 425.1548. The nucleoside symmetrical disulfide 5 formed
under these conditions was isolated (65%).
4.1.16. 5-Bromo-20,30-dideoxy-30-(2-(trimethylsilyl)ethyl)
thiouridine (24) and bis-(20,30-dideoxy-5-bromouridin-30-yl)
disulfide (25)
To a solution of 10 (150 mg, 0.44 mmol) in dry dichloromethane
(4 mL) was added cyanogen bromide (230 mg, 2.17 mmol). The
solution was stirred under argon at 40 °C for 96 h, then hydrolyzed
with a phosphate buffer solution (0.5 M, pH 7, 2 mL) for 30 min,
and concentrated to dryness. The residue was chromatographed
on silica gel in dichloromethane/methanol (98:2 then 95:5) to give
the symmetrical disulfide 25 (27 mg, 0.04 mmol, 25%) and com-
pound 24 (42 mg, 0.10 mmol, 21%) as white powders. Compound
24: mp 81–83 °C; 1H NMR (400 MHz, CDCl3) d 8.41 (1H, s, 6-H),
6.09 (1H, dd, J = 6.7 Hz, J = 3.2 Hz, 10-H), 4.14 (1H, s, 50-H), 4.93
(2H, m, 40-H, 50-H), 3.95 (1H, m, 30-H), 2.66 (2H, m, S–CH2), 2.60–
2.44 (2H, m, 20-H ꢁ 2), 1.28 (1H, t, 50-OH), 0.88 (2H, m, CH2–Si),
ꢀ0.02 (9H, s, Si(CH3)3); 13C NMR (100 MHz, CDCl3) d 158.8 (C2),
149.3 (C4), 140.4 (C6), 96.1 (C5), 86.3 (C10), 86.2 (C40), 60.8 (50-
CH2), 41.2 (20-CH2), 39.6 (C30), 27.6 (S–CH2), 17.5 (CH2–Si), ꢀ1.5
(Si(CH3)3); MS (FAB+, NBA) m/z 423 [M+H]+; HRMS for
4.1.13. 20,30-Dideoxy-30-(2-hydroxyethyldithio)thymidine (21)
Compound 21 (41 mg, 0.12 mmol, 50%) was obtained as a white
powder from 16 (100 mg, 0.24 mmol), mercaptoethanol (170 lL,
2.43 mmol), imidazole buffer (10ꢀ3 M, pH 6.0, 5 mL), and a mixture
of THF/imidazole buffer (2.5/2.5 mL), 15 h; mp 58–61 °C; 1H NMR
(400 MHz, CDCl3) d 8.25 (1H, s, NH), 7.59 (1H, s, 6-H), 6.08 (1H,
dd, J = 5.2 Hz, J = 6.4 Hz, 10-H), 4.12–4.00 (3H, m, 40-H, 50-H ꢁ 2),
3.94 (2H, m, CH2–OH), 3.73 (1H, m, 30-H), 3.01–2.93 (2H, m,
CH2–S), 2.54 (2H, m, 20-H ꢁ 2), 1.94 (3H, s, 5-CH3); 13C NMR
(100 MHz, CDCl3) d 165.0 (C2), 150.8 (C4), 136.8 (C6), 109.7 (C5),
85.6 (C40), 84.5 (C10), 60.6 (50-CH2), 59.8 (CH2–OH), 45.4 (C30),
41.8 (CH2–S), 37.9 (20-CH2), 11.0 (5-CH3); MS (DCI, NH3-isobutane)
C
14H22N2O79BrNa2SiS, [M+2Na]+, calculated 467.0048, found
4
467.0049. 25: 1H NMR (400 MHz, CDCl3) d 8.63 (1H, s, 6-H), 6.12
(1H, dd, J = 6.5 Hz, J = 4.0 Hz, 10-H), 4.05 (1H, s, 40-H), 3.97 (1H,
dd, J = 2.4 Hz, J = 12.3 Hz, 50-H), 3.86 (1H, dd, J = 2.7 Hz,
J = 12.3 Hz, 50-H), 3.66 (1H, m, 30-H), 2.61 (2H, m, 20-H ꢁ 2); 13C
NMR (100 MHz, CDCl3) d 160.3 (C2), 150.1 (C4), 140.7 (C6), 96.3
(C5), 86.2 (C10), 85.3 (C40), 60.0 (50-CH2), 45.3 (20-CH2), 38.3 (C30);