Table 3. In vitro evaluation of selected compounds against asexual blood stage of P. falciparum 3D7 and W2 strains, cytotoxicity on mammalian cells (COS7), and selectivity indices.
| Compound | EC50 (Pf3D7) (μM) |
EC50 (PfW2) (μM) |
CC50 (COS-7) (μM) | SIa | SIb |
|---|---|---|---|---|---|
| LabMol-148 | >40 | >40 | >200 | − | − |
| LabMol-149 | 1.450 ± 0.524 | 0.509 ± 0.177 | >100 | >71.4 | >196 |
| LabMol-150 | >40 | >40 | >200 | − | − |
| LabMol-151 | 1.911 ± 0.292 | 1.616 ± 0.321 | 140.8 ± 11.2 | 73.7 | 87.1 |
| LabMol-152 | 0.049 ± 0.029 | 0.078 ± 0.014 | 16.7 ± 10.3 | 340.8 | 214.1 |
| Chloroquine | 0.011 ± 0.001 | 0.173 ± 0.020 | >50 | 4,545 | 289 |
| Pyrimethamine | 0.037 ± 0.007 | 18.240 ± 4.537 | >100 | 2,702 | 5.5 |
EC50: half maximal effective concentration on 3D7 and W2 Plasmodium falciparum strains; CC50: half maximal cytotoxic concentration on COS7 cells; COS7: fibroblast-like cells derived from monkey kidney tissue; SIa: Selectivity index calculated by COS7 CC50/3D7 EC50; and SIb: Selectivity index calculated by COS7 CC50/W2 EC50; The data are expressed as mean ± SD of three independent assays. Dashed SI values means that SI could be calculated because compounds did not show activity even at highest concentrations used in the assay.