TABLE II. Selectivity indexes (SI), the ratio between in vitro cytotoxicity [minimum lethal dose for 50% of the cells (MLD50)] and activity [inhibitory concentration for 50% (IC50), mM] against Plasmodium falciparum (Pf) of tamoxifen-like compounds and metallic derivatives.
| Compounds/ | Structural | MLD50 | IC50 | SI |
|---|---|---|---|---|
| series | class | HepG2a | Pf | (MLD50/IC50) |
| 1/A | Tamoxifen-like | > 3516 | 83 ± 5 | 42 |
| 2/A | < 10 | 2.2 ± 0.05 | Toxic | |
| 3/B | Ferrocifene | 479 ± 89 | 16.6 ± 2.3 | 29 |
| 4/B | < 7.7 | 0.7 ± 0.1 | Toxic | |
| 5/B | < 61 | 23.6 ± 9.8 | Toxic | |
| 6/B | < 61 | 23.6 ± 5.9 | Toxic | |
| 7/C | [3]ferrocenophane | > 2562 | 62.8 ± 10.7 | 41 |
| 8/C | < 63 | 5.9 ± 1.6 | 18 | |
| 9/D | Di-ferrocenyl derivative | < 60 | 27.1 ± 23.2 | Toxic |
| 10/D | < 60 | 7.8 ± 1.6 | Toxic | |
| 11/E | Ruthenocene | 2248 ± 53 | 16.5 ± 0.5 | 136 |
| 12/E | 251 ± 34 | 4.7 ± 1.3 | 53 | |
| 13/E | 266 ± 3 | 5.9 ± 2.3 | 45 | |
| CQ | Quinoline | 502 ± 52 | 0.1 ± 0.02 | 5,020 |
a: except for compounds 12 and 13, which were tested for cytotoxicity against normal monkey kidney cells using the neutral red method; CQ: chloroquine.