Table 1.
Antiviral activity and cytotoxicity of benzimidazole derivatives (1–7c, 1–7d, 1–7e); NM108 and ribavirin were used as positive controls.
| ||||||
|---|---|---|---|---|---|---|
| Compound | R1 | R2 | R’ | MDBK CC50 a |
BVDV EC50 b |
S.I. |
| 1c | H | H | 3,4,5-tri-OCH3 | 28.5 | 2.2 | 12.9 |
| 1d | H | H | 4-NO2 | >100 | >100 | - |
| 1e | H | H | 4-Cl | >100 | >100 | - |
| 2c | Cl | H | 3,4,5-tri-OCH3 | 45 | 0.09 | 500 |
| 2d | Cl | H | 4-NO2 | >100 | 1.9 | >52.6 |
| 2e | Cl | H | 4-Cl | >100 | >100 | - |
| 3c | Cl | Cl | 3,4,5-tri-OCH3 | 28 | 1.3 | 21.5 |
| 3d | Cl | Cl | 4-NO2 | >100 | 53 | >1.9 |
| 3e | Cl | Cl | 4-Cl | 60 | >60 | - |
| 4c | F | H | 3,4,5-tri-OCH3 | >100 | 41 | >2.4 |
| 4d | F | H | 4-NO2 | >100 | 7.9 | >12.7 |
| 4e | F | H | 4-Cl | >100 | >100 | - |
| 5c | F | F | 3,4,5-tri-OCH3 | >100 | 1.4 | >71.4 |
| 5d | F | F | 4-NO2 | >100 | 3.6 | >27.8 |
| 5e | F | F | 4-Cl | >100 | >100 | - |
| 6c | CH3 | H | 3,4,5-tri-OCH3 | >100 | 0.23 | >434.8 |
| 6d | CH3 | H | 4-NO2 | >100 | >100 | - |
| 6e | CH3 | H | 4-Cl | >100 | >100 | - |
| 7c | CH3 | CH3 | 3,4,5-tri-OCH3 | >100 | 0.3 | >333.3 |
| 7d | CH3 | CH3 | 4-NO2 | >100 | >100 | - |
| 7e | CH3 | CH3 | 4-Cl | >100 | >100 | - |
| NM 108 | >100 | 1.5 | >66.7 | |||
| Ribavirin | >100 | 18 | >5.6 | |||
a Compound concentration (µM) required to reduce the viability of mock-infected MDBK cells by 50%, as determined using the MTT method. b Compound concentration (µM) required to achieve 50% protection of MDBK cells from the BVDV-induced cytopathogenicity, as determined using the MTT method. In bold relevant EC50 values and significant S. I.