Table 2.

IC₅₀ values of 4-aminoquinolines (11 and 16), (aminomethyl)quinolines (12 and 17) and 1-azabicyclo[2.2.1]heptane 7 tested for their in vitro antiplasmodium activity against a CQ-sensitive (NF54) and a CQ-resistant (K1) P. falciparum strain and their cytotoxicity. Data are expressed as mean ± SD values of three independent experiments.

Compound	NF54 IC50 (μM)	K1 IC50 (μM)	CHO IC50 (μM)	SIa	RIb
11ad	0.021 ± 0.0050	0.033 ± 0.0062	26.0 ± 2.9	1266	1.6
11be	0.045 ± 0.007	0.069 ± 0.0113	11.2 ± 2.1	250	1.5
12ac	6.77 ± 0.25	–	–	–	–
12bc	4.07 ± 0.74	–	–	–	–
12cc	1.27 ± 0.04	–	–	–	–
12dc	0.72 ± 0.03	4.64 ± 0.13	102.65 ± 19.67	142	6.4
12ec	3.60 ± 0.31	–	–	–	–
16ad	0.012 ± 0.0010	0.026 ± 0.0057	121.8 ± 41.4	10,149	2.2
16bd	0.015 ± 0.0017	0.025 ± 0.0089	29.9 ± 1.2	1991	1.7
16ce	0.236 ± 0.032	0.0685 ± 0.0078	27.0 ± 3.2	114	0.3
17ad	2.37 ± 1.05	3.66 ± 0.43	139.4 ± 14.1	59	1.5
17bd	4.94 ± 1.18	–	–	–
17cd	1.57 ± 0.17	2.82 ± 0.14	210.6 ± 31.4	134	1.8
17dd	3.66 ± 0.82	–	–	–	–
17ed	2.89 ± 1.06	–	–	–	–
17fd	1.28 ± 0.33	1.95 ± 0.078	199.0 ± 23.3	156	1.5
17gd	7.75 ± 1.44	–	–	–	–
17hd	17.99 ± 2.44	–	–	–	–
7c	1.55 ± 0.13	–	–	–	–
Chloroquine	0.011 ± 0.001c 0.010 ± 0.0004d 0.020 ± 0.001e	0.167 ± 0.028c 0.169 ± 0.047d 0.169 ± 0.047e	–	–	14.7 17.8 8.5
Emetine	–	–	0.04 ± 0.01c 0.14 ± 0.04d 0.03 ± 0.01e	–	–

-: not tested.

^aSI (selectivity index) = IC₅₀ CHO/IC₅₀ NF54.

^bRI (resistance index) = IC₅₀ K1/IC₅₀ NF54.

^cReference values: CQ: IC₅₀ (NF54) 11.3 ± 1.0 nM, IC₅₀ (K1) 166.5 ± 27.9 nM; emetine: IC₅₀ 0.04 ± 0.01 μM.

^dReference values: CQ: IC₅₀ (NF54) 9.5 ± 0.4 nM, IC₅₀ (K1) 169.0 ± 46.7 nM; emetine: IC₅₀ 0.14 ± 0.04 μM.

^eReference values: CQ: IC₅₀ (NF54) 20.0 ± 1.4 nM, IC₅₀ (K1) 169.0 ± 46.7 nM; emetine: IC₅₀ 0.03 ± 0.01 μM.