4-Arylthieno[2,3-<i>b</i>]pyridine-2-carboxamides Are a New Class of Antiplasmodial Agents

• Main Authors: Sandra I. Schweda, Arne Alder, Tim Gilberger, Conrad Kunick
• Format: Article
• Language: English
• Published: MDPI AG 2020-07-01
• Series: Molecules
• Subjects: anti-malarial drugs; antiplasmodial; malaria; <i>Pf</i>GSK-3; <i>Plasmodium falciparum</i>; thieno[2,3-<i>b</i>]pyridine
• Online Access: https://www.mdpi.com/1420-3049/25/14/3187

Malaria causes hundreds of thousands of deaths every year, making it one of the most dangerous infectious diseases worldwide. Because the pathogens have developed resistance against most of the established anti-malarial drugs, new antiplasmodial agents are urgently needed. In analogy to similar antiplasmodial ketones, 4-arylthieno[2,3-<i>b</i>]pyridine-2-carboxamides were synthesized by Thorpe-Ziegler reactions. In contrast to the related ketones, these carboxamides are only weak inhibitors of the plasmodial enzyme <i>Pf</i>GSK-3 but the compounds nevertheless show strong antiparasitic activity. The most potent representatives inhibit the pathogens with IC₅₀ values in the two-digit nanomolar range and exhibit high selectivity indices (>100).