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Identification and Mechanistic Evaluation of Hemozoin-Inhibiting Triarylimidazoles Active against Plasmodium falciparum.

ABSTRACT: In a previous study, target based screening was carried out for inhibitors of ?-hematin (synthetic hemozoin) formation, and a series of triarylimidazoles were identified as active against Plasmodium falciparum. Here, we report the subsequent synthesis and testing of derivatives with varying substituents on the three phenyl rings for this series. The results indicated that a 2-hydroxy-1,3-dimethoxy substitution pattern on ring A is required for submicromolar parasite activity. In addition, cell-fractionation studies revealed uncommonly large, dose-dependent increases of P. falciparum intracellular exchangeable (free) heme, correlating with decreased parasite survival for ?-hematin inhibiting derivatives.

SUBMITTER: Wicht KJ

PROVIDER: S-EPMC5304302 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Identification and Mechanistic Evaluation of Hemozoin-Inhibiting Triarylimidazoles Active against <i>Plasmodium falciparum</i>.

Wicht Kathryn J KJ Combrinck Jill M JM Smith Peter J PJ Hunter Roger R Egan Timothy J TJ

ACS medicinal chemistry letters 20170124 2

In a previous study, target based screening was carried out for inhibitors of β-hematin (synthetic hemozoin) formation, and a series of triarylimidazoles were identified as active against <i>Plasmodium falciparum</i>. Here, we report the subsequent synthesis and testing of derivatives with varying substituents on the three phenyl rings for this series. The results indicated that a 2-hydroxy-1,3-dimethoxy substitution pattern on ring A is required for submicromolar parasite activity. In addition, ...[more]

PMID: 28197312

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