Table 2.
Antimycobacterial activity of compounds 4a–4j and 5a–5j compared to isoniazid and rifampicin.
| Compd. | R | % Inhibition at 6.25 μg/mL | MIC90 (μg/mL) | CC50 (μg/mL) | SI |
|---|---|---|---|---|---|
| 4a | 2-OH | 76 | ND | ND | ND |
| 5a | 2-OH | 50 | ND | ND | ND |
| 4b | 3-OH | 0 | ND | ND | ND |
| 5b | 3-OH | 0 | ND | ND | ND |
| 4c | 4-OH | 59 | ND | ND | ND |
| 5c | 4-OH | 35 | ND | ND | ND |
| 4d | 3-OCH3, 4-OH | ND | ND | ND | ND |
| 5d | 3-OCH3, 4-OH | 20 | ND | ND | ND |
| 4e | 2-OCH3 | ND | ND | ND | ND |
| 5e | 2-OCH3 | 71 | ND | ND | ND |
| 4f | 4-OCH3 | ND | ND | ND | ND |
| 5f | 4-OCH3 | ND | ND | ND | ND |
| 4g | 2-NO2 | 97 | 6.25 | 0.84 | 0.13 |
| 5g | 2-NO2 | 57 | ND | ND | ND |
| 4h | 3-NO2 | 0 | ND | ND | ND |
| 5h | 3-NO2 | 0 | ND | ND | ND |
| 4i | 4-NO2 | 91 | 6.25 | 1.14 | 0.18 |
| 5i | 4-NO2 | 100 | >6,25 | ND | ND |
| 4j | 4-Cl | 0 | ND | ND | ND |
| 5j | 4-Cl | 12 | ND | ND | ND |
| isoniazid | ND | 0.025–0.05 | >1000 | >40,000 | |
| rifampicin | 98 | 0.015–0.125 | >100 | >800 | |
Note: ND = not determined.