512
K. Li et al. / Bioorg. Med. Chem. 10 (2002) 507–515
from the Southern New England Ultraviolet Company
(Branford, CT, USA). Samples were photolyzed in
1.0 mL water jacketed quartz cells. Liquid scintillation
counting was conducted in a Packard 1900 TR liquid
scintillation counter (Meridian, CT, USA). SDS gel
electrophoresis was performed on a Protean II unit and
gels were dried on a Model 543 gel drier, both from
BioRad (Richmond, CA, USA). X-ray films were
developed using an X-Omat developer (AFP Imaging,
Elmsford, NY, USA).
2-(4-Fluorophenylacyl)-thio-1,N6-etheno-20-deoxyadeno-
sine 50-monophosphate (5m). This was prepared from
ammonium 2-thio-1,N6-etheno-20-deoxyadenosine 50-
monophosphate (4, 120 mg, 0.29 mmol) and a-bromo-4-
fluoroacetophenone (69 mg, 0.32 mmol) as described
above for the synthesis of 2, yielding 140 mg (92%) of
pure 5m. H NMR (DMSO) d 1.95 (m, 1H, 20H1), 2.52
1
(m, 1H, C20H), 3.80 (t, 2H, C50H), 4.10 (m, 1H, C40H),
5.10 (m, 1H, C30H), 6.00 (t, 1H, C110H), 6.90 (m, 2H, Ph
H), 7.30 (m, 2H, PhH), 7.60 (d, 1H, C10H), 7.92 (s, 1H,
C11H), 8.30 (s, 1H, C8H). High resolution MS (+FAB,
glycerol) m/e 524.0804; calcd for C20H20N5O7SFP
(M+H+), 524.0805.
Ammonium 2-(4-azidophenacyl)thio-1,N6-etheno-20-deoxy-
adenosine 50-monophosphate (1m). The tetrabutyl-
ammonium salt of 2-thio-1,N6-etheno-dAMP (120 mg,
0.29 mmol) in water (2 mL) was added to a solution of
para-azidophenacyl bromide (78 mg, 1.1 equivalent) in
acetonitrile (2 mL) in a brown reacti-vial. The pH of the
solution was adjusted to 8 using KOH (6 N); the result-
ing clear yellow solution was purged with nitrogen and
stirred at room temperature for 3 h. The reaction mix-
ture was then diluted with water (10 mL), acidified to
pH 4 with HCl (1N), and extracted with three volumes
of ethyl ether. The aqueous phase was neutralized with
1N NaOH, and the product was purified by preparative
HPLC on a C18 column using a 30 min linear gradient
from 0 to 50% acetonitrile in 10 mM ammonium ace-
tate. Collection and lyopholization of the major peak
with a retention time of 29 min afforded 52.3 mg (50%)
of 1m: IR (KBr) 2116 (N3); UV lmax (eꢂ10ꢀ4): H2O, 297
2-(4-N-acetylamino-phenylacyl)-thio-1,N6 -etheno-20 -
deoxyadenosine 50-monophosphate (6m). This was pre-
pared from triethylammonium 2-thio-1,N6-etheno-20-
deoxyadenosine
50-monophosphate
(4,
100 mg,
0.26 mmol) and a-bromo-4-N-acetylamino-acetophen-
one (73.2 mg, 0.28 mmol) using the method described
above for the synthesis of 2, yielding 95 mg (66%) of
pure 6m. 1H NMR (DMSO) d 2.02 (s, 3H, CH of
amide), 2.12 (m, 1H, 20H1), 2.52 (m, 1H, C20H), 3.85 (t,
2H, C50H), 4.15 (m, 1H, C40H), 4.78 (s, 2H, CH of
ketone), 5.10 (m, 1H, C30H), 6.10 (t, 1H, C10H), 7.60 (d,
1H, C10H), 7.80 (m, 2H, Ph H), 7.92 (s, 1H, C11H),
8.10 (m, 2H, PhH), 8.40 (s, 1H, C8H). High-resolution
MS (+FAB, glycerol) m/e 563.1103; calcd for
C22H24N6O8SP (M+H+), 563.1114.
(1.61); H NMR (D2O) d 2.08 (m, 1H, C20H1), 2.62 (m,
1
1H, C20H2), 3.86 (br s, 2H, C50H), 4.33 (br s, 1H, C40H),
4.78 (br s, 1H, C30H), 5.70 (t, J=6.3 Hz, 1H, C10H), 7.10
(d, J=8.4 Hz, 2H, PhH), 7.71 (s, 1H, C10H), 7.53 (s, 1H,
C11H), 7.98 (d, J=8.4 Hz, 2H, PhH), 8.25 (s, 1H, C8H).
High-resolution FABMS (glycerol) m/e 545.0772, calcd
for C20H18N8O7PS (MꢀH+), 545.0757.
2-(4-Trifluoromethylphenylacyl)-thio-1,N6-etheno-20-deoxy-
adenosine 50-monophosphate (7m). This was prepared
from triethylammonium 2-thio-1,N6-etheno-20-deoxy-
adenosine 50-monophosphate (4, 100 mg, 0.26 mmol)
and a-bromo-4-trifluoromethylacetophenone (86.1mg,
0.32 mmol) using the method described above for the
synthesis of 2, yielding 53 mg (36%) of pure 7m. 1H
NMR (DMSO) d 1.92 (m, 1H, 20H1), 2.50 (m, 1H,
C20H), 3.45 (t, 2H, C50H), 4.10 (m, 1H, C40H), 5.10 (m,
1H, C30H), 5.25 (s, 2H, CH2), 6.00 (t, 1H, C10H), 7.60
(m, 2H, Ph H), 7.95 (m, 2H, PhH), 8.12 (d, 1H, C10H),
8.33 (s, 1H, C11H), 8.85 (s, 1H, C8H). High resolution
MS (+FAB, glycerol) m/e 574.0776; calcd for
C21H20N5O7SF3P (M+H+), 574.0773.
2-(2,3,5,6-Tetrafluoro-4-azidophenacyl)-thio-1,N6-etheno-
20 deoxyadenosine 50-monophosphate (2m). Triethyl-
ammonium 2-thio-1,N6-etheno-20-deoxyadenosine 50-
monophosphate (4, 276 mg, 0.4 mmol) in water (10 mL)
was added to a solution of a-bromo-4-azido-2,3,5,6 tet-
rafluoroacetophenone (136 mg, 0.44 mmol) in acetoni-
trile (2 mL). The pH of the solution was adjusted to 7.0
using 0.2 N HCl. The reaction mixture was stirred at
room temperature for 1h. The solvents were removed
under vacuum, and the resulting residue was dissolved
in water (10 mL). The aqueous solution was washed
with methylene chloride. The aqueous layer was sepa-
rated and lyophilized to dryness to give the crude pro-
duct. The crude product was purified on a reverse-phase
C18 HPLC column using a 30 min gradient from 0 to
50% acetonitrile in 0.1% TFA. Collection and lyopho-
lization of appropriate fractions afforded 50.3 mg (50%)
of the product as a off-white solid: IR (cmꢀ1, KBr) 2112
(N3); UV lmax (eꢂ10ꢀ4): H2O, 310 (2.01); 1H NMR
(DMSO) d 2.35 (m, 1H, 20H1), 2.56 (m, 1H, C20H), 3.94
(t, 2H, C50H), 4.35 (m, 1H, C40H), 4.89 (m, 1H, C30H),
6.15 (t, 1H, C10H), 7.70 (d, 1H, C10H), 8.02 (d, 1H,
C11H), 8.42 (s, 1H, C8H); 19FNMR (DMSO) d
ꢀ141.38 (dd, 2F), ꢀ151.75 (dd, 2F); High-resolution
MS (+FAB, glycerol) m/e 619.0519; calcd. for
C20H16N5O7SF4P (M+H+), 619.0536.
2-(3-phenyl-2-propanonyl)-thio-1,N6-etheno-20-deoxyade-
nosine 50-monophosphate (8m). This was prepared from
triethylammonium 2-thio-1,N6-etheno-20-deoxyadeno-
sine 50-monophosphate (4, 138 mg, 0.2 mmol) and ben-
zyl chloromethyl ketone (36.9 mg, 0.22 mmol) as
described above for the synthesis of 2, yielding 41.8 mg
1
(41%) of pure 8m. H NMR (DMSO) d 2.35 (m, 1H,
20H1), 2.68 (m, 1H, C20H), 3.88 (t, 2H, C50H), 3.98 (m,
1H, C40H), 4.06 (s, 2H, CH of benzyl), 4.42 (m, 1H,
C30H), 6.12 (t, 1H, C10H), 7.18 (d, 3H, PhH), 7.62 (d,
1H, C10H), 7.95 (s, 1H, C11H), 8.40 (s, 1H, C8H); MS
(-FAB, glycerol) m/e 517 (MꢀH+).
2-(2,3,5,6-Tetrafluoro-4-azidophenacyl)-thio-1,N6-etheno-
20-deoxyadenosine 50-triphosphate (2). The triphosphate 2
was prepared from 2-(2,3,5,6-tetrafluoro-4-azidophena-
cyl)-thio-1,N6-etheno-20-deoxyadenosine 50-monopho-
sphate (2m) by a previously published procedure.18