Table 1.
Activity of thymidine analogs against vaccinia virus and cowpox virusa.
| Compound | Vaccinia virus (EC50, μM)b | Cowpox virus (EC50, μM) | Cytotoxicity (CC50, μM) |
|---|---|---|---|
| cidofovir | 19 ± 11 | 29 ± 6.1 | >317 ± 0 |
| idoxuridine | 8.4 ± 3.3 | 3.7 ± 2.7 | >100 ± 0 |
| fialuridine | 1.5 ± 0.4 | 0.2 ± 0.1 | >100 ± 0 |
| (N)-MCT | 0.6 ± 0.1 | 1.5 ± 1.2 | >100 ± 0 |
| 5-iodo-4′-thio-2′-deoxyuridine (4′-thioIDU) | 0.5 ± 0.2 | 0.1 ± 0.04 | >100 ± 0 |
| 1-(2-deoxy, 4′thio-β-D-ribofuranosyl)-thymidine | 0.03 ± 0.01 | 0.02 ± 0.01 | 29 ± 4.0 |
| 4-thio-β-D-arabinofuranosyl)-cytidine | 0.3 ± 0.2 | 1.6 ± 0.8 | 53 ± 6.4 |
| 1-(4-thio-β-D-arabinofuranosyl)-5-fluoro cytidine | 0.1 ± 0.01 | 0.4 ± 0.1 | 4.6 ± 1.1 |
| 5-iodo-4-thio-3′,5′-di-O-acetyl-2′-deoxyuridine | 0.9 ± 0.3 | 0.3 ± 0.2 | >80 ± 28 |
| 5-bromo-4′-thio-2′-deoxyuridine | 0.1 ± 0.02 | 0.05 ± 0.04 | >100 ± 0 |
| 5-trifluoromethyl-2′-deoxy-4′-thiouridine | 0.1 ± 0.004 | 0.1 ± 0.01 | >100 ± 0 |
a
Adapted from [25]
b
Concentration of compound sufficient to reduce viral replication by 50% (EC50).