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Table 2. Anti-HIV-1 IIIB activity in MT-4 cells
Compound
Tenofovir DF
2.31
Emtricitabine
27.7
5a
5ba
5c
5d
5e
5f
5g
5h
5i
5j
IC50 (lM)
>30
3.51
17.5
23.1
>30
>30
1.61
>30
>30
23.7
a Exhibited cell toxicity under 10 lg/ml concentration.
Tenofovir DF (used as positive controls) in 2.2.15 cells
(an HBV-transfected human HepG2 cell line) in vitro
was tested. The 2.2.15 cells were seeded in 96-well plate
and treated with the test compounds at 37 ꢁC for 9 days.
Then the cells were harvested and intracellular DNA
was extracted. Inhibition of the viral replicative interme-
diate DNA in compound-treated cells versus untreated
cells was determined. Cell viability was assessed by the
MTT assay. The 50% inhibitory concentration (IC50)
and 50% toxic concentration (TC50) of the test com-
pounds are reported in Table 1.
potent antiviral effect in vitro. The antiviral effect indi-
cated that 5f and 5g exhibited favorable anti-HBV and
anti-HIV-1 activity, respectively, and they are both
promising for further studies.
Acknowledgment
This work was supported in part by grants from the Na-
tional Basic Research Program of China (973 program,
2004CB518900).
Among the tested compounds, the best anti-HBV activ-
ity was exhibited by 5f with an IC50 of 2.15 lM, superior
to not only PMEA and PMPA, but also Tenofovir DF
(IC50 = 5.10 lM); The anti-HBV activity of 5c–e (IC50
ranging from 5.33 to 5.94 lM) were similar to Tenofovir
DF. 5a–b, 5g–h, and 5j exhibited cell toxicity in low con-
centration (ranging from 2.46 to 10.6 lM).
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Based on the above activity results, some comments
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The results showed that all compounds possess anti-
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´
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