Table 2.
Efficacies of bromophycolide A (1), 18-acetylbromophycolide A (7), and amodiaquine (AMQ) against three P. falciparum strains, along with their activity in inhibiting heme crystallization, and cytotoxicity against uninfected cell lines.
| Compound | Antiplasmodial activity IC50 [nM] | Heme crystallization IC50 [mol equiv][c] | Cytotoxicity IC50 [μM] | ||||
|---|---|---|---|---|---|---|---|
| 3D7[a] | Dd2[b] | HB3[a] | Vero | J774 | HepG2 | ||
| 1 | 499 ± 51 | 377 ± 92 | 493 ± 44 | 2.5 ± 0.13 | 34.6 | 19.0 | 21.3 |
| 7 | 241 ± 52 | 304 ± 8.4 | 431 ± 25 | 2.0 ± 0.15 | 74.0 | 24.7 | 38.5 |
| 8 | 14 800 ± 1200 | 4880 ± 1100 | 6050 ± 440 | >6.0 | – | – | – |
| AMQ | 7.8[d] | – | 8.5[d] | 1.2 ± 0.19 | – | – | – |
[a]
3D7 and HB3 are chloroquine-sensitive parasites.
[b]
Dd2 is a chloroquine-resistant parasite.
[c]
IC50 values[19] are reported as molar equivalents of bromophycolide to heme.
[d]
Values for AMQ are reported from Hawley et al.[30]
[e]
A true IC50 value could not be determined due to solubility limitation above 6 mol equiv.