4-(2-Oxopropylamino)-1-(b-D-arabinofuranosyl)pyrimidine-2-
(1H)-one (4) (oxo-ara-C). 2 (20 mg 0.058 mmol) was hydrolyzed
by treatment with aqueous 1 M oxalic acid in THF (0.3 ml) at
room temperature for 5 h. The solvent was evaporated under
reduced pressure and the crude product was purified by column
chromatography (SiO2 1% Et3N, 12% methanol-chloroform) to
give oxo-ara-C (7.7 mg, 44%) as a white solid; mp 180–182 ◦C;
1H NMR (CD3OD, 300 MHz) d 7.79 (d, 1H, J = 7.5 Hz), 6.15
(d, 1H, J = 3.8 Hz), 5.93 (d, 1H, J = 7.5 Hz), 4.26 (s, 2H), 4.16
(dd, 1H, J = 2.4, 3.6 Hz), 4.04 (dd, 1H, J = 2.8, 2.6 Hz), 3.92 (m,
1H), 3.79 (m, 2H), 2.18 (s, 3H); 13C NMR (CD3OD, 75.5 MHz) d
206.0, 165.6, 158.5, 143.4, 95.4, 88.4, 86.6, 78.2, 76.8, 62.8, 51.3,
27.1; FABMS (glycerol) m/z 300 [(M + H)+]; HRMS calcd. for
C12H18N3O6 [(M + H)+] 300.1196, found 300.1189.
under aerobic or hypoxic conditions using Anaeron Pack System
(Mitsubishi Gas Chemical Company Inc., Japan) were treated
with X-rays at a dose of 4 Gy and incubated for 72 hours under
aerobic conditions. After adding 12 mL of Cell Count Reagent SF
solution (Nacalai, Japan) to each well, and the cell viability assay
was performed as described above.
References
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G(∑H) = 60 nmol J-1.
Assessment of cytotoxicity toward A549 cells
A549 cells were cultured in Dulbecco’s modified Eagle’s minimum
essential medium (DMEM) containing 10% fetal bovine serum
(FBS). The cells were seeded into 96-well plates (2000 cells/well)
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under aerobic conditions for 72 hours, and added with 11 mL of
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incubated at 37 ◦C for 2 hours and the cell viability assay was
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Radiation-induced cytotoxicity of oxo-ara-C
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∑
produce hydroxyl radicals, as follows: eaq-+ N2O → OH + OH- + N2
(k = 9.1 ¥ 109 dm3 mol-1 s-1).
A549 cells were seeded into 96-well plates (2000 cells/well) and
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cells were treated in a hypoxic chamber, BACTRON-II(Sheldon
Manufacturing Inc., Cornelius, OR, USA). The plates kept
14 Without X-ray treatment, the effect of oxygen on the cell viability
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654 | Org. Biomol. Chem., 2009, 7, 651–654
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