Table 1.

Chemical structures of investigated 3-alkoxy-1,2-dioxolanes and determined IC₅₀ values (mean of three experiments) against newly transformed schistosomula (NTS) and adult S. mansoni 72 h post-compound exposure; r represents goodness of fit (conformity with r ≥ 0.85)

Compound					IC50 (μM) for S. mansoni
	R1	R2	R3	R	NTS	r	adult	r
1	Me	Me	Me		31.1	0.9	11.9	1.0
2	Me	Bu	Me	CH2CH2Ph	7.5	1.0	12.4	1.0
3	-(CH2)5-		CH2CH2Ph	CH2CH2Ph	4.2	0.9	20.1	0.8
4	Me	Me	CH2Ph	Me	101.0	0.7	49.2	1.0
5					17.0	0.7	76.4	1.0
6	Me	Me	Me	5,6-epoxyhexyl	35.9	0.9	101.5	1.0
7	Me	Me	Me	CH2CH2CN	89.2	1.0	137.0	1.0
8	-(CH2)5-		Me	CH(OH)CH2OH	90.9	0.9	138.4	1.0
9	Me	Me	Me	(CH2)9CO2Me	89.7	0.9	169.3	0.9
10	Me	Me	Me	CH2CH2CO2Me	76.0	1.0	206.2	1.0
11	Me	Me	Me	CH2CH2OMe	69.2	0.8	207.4	0.9
12	Me	Me	Me	CH2CH2 CH2OH	42.6	0.8	235.8	0.9
13	Me	Me	Me	(CH2)4CO2Me	59.8	1.0	283.3	0.6
14	Me	Me	Me	CH(OH)CH2OH	102.5	0.9	>436
15	Me	Me	Me	CH2CH2Ph	2.7	0.9	58.4	0.9
16	-(CH2)5-		Me	CH2CH2Ph	2.8	0.9	49.4	0.9
17	-(CH2)5-		Me		4.1	0.9	71.8	1.0
18	Me	Me	Me		4.8	0.9	109.3	0.9
Praziquantel					2.2	0.9	0.08a
Artesunate					5.0	0.9	41.2	0.8

^aAs described by Keiser et al.²⁶