Macrolides rapidly inhibit red blood cell invasion by the human malaria parasite, Plasmodium falciparum

Table 1 Growth/invasion inhibitory activity of compounds described in this study

Compound number	Compound abbreviation	Compound name	Lactone ring size	IIA IC₅₀ (μM)	40 hour IC₅₀ (μM)	90 hour IC₅₀ (μM)	120 hour IC₅₀ (μM)
1	AZR^a	Azithromycin	15	10	6	7	0.04
2	AZR-desclad^a	-	15	50	39	31	ND
3	AZR-desglycan^a	-	15	>1,600	>500	285	ND
1	AZR^b	Azithromycin	15	38	12	7	0.1
4	12e^b,c	-	15	15	1	0.6	0.16
5	1j^b,c	-	15	7	0.9	0.7	0.16
6	11c^b,d	-	15	28	ND	0.9	ND
7	7/47^b,e	-	15	52	ND	5	ND
8	7/25^b,e	-	15	73	ND	10	ND
9	ERY^a	Erythromycin	14	420	230	52	ND
10	ERY-desclad^a	-	14	ND	288	185	ND
11	ERY-oxime^a	-	14	150	85	24	ND
12	ROX^a	Roxithromycin	14	83	70	27	ND
13	DIR^a	Dirithromycin	14	521	15	8	ND
14	Meg-ERY^a,f	6-0-megosaminyl-erythromycin	14	13	ND	ND	ND
15	SPI^a	Spiramycin	16	123	15	13	ND
16	CLI^a	Clindamycin	NA	743	ND	ND	ND
D10-AZR^r (delayed death, resistant) comparison
1	AZR^a	Azithromycin	15	-	-	-	0.16^g,h
1^g	AZR^a	Azithromycin	15	25	ND	ND	9^h

^aVehicle was ethanol; ^bvehicle was dimethyl sulfoxide (DMSO); ^cfrom Bukvic et al. [44]; ^dfrom Peric et al. [42]; ^efrom Hutinec et al. [43]; ^ffrom Goodman et al. [41]. All IC₅₀s are for the D10-PfPHG line used throughout this study, with the exception of ^gwhich were undertaken with the D10 azithromycin-resistant line (D10-AZR^r) made as per Goodman et al. [41]. All assays were measured by flow cytometry, with the exception of ^hwhich were measured by hypoxanthine uptake assays. Desclad, descladinosyl; desglycan, descladinosyl and desosaminyl; NA, not applicable; ND, not done

ISSN: 1741-7007