Structure-Guided Lead Optimization of Triazolopyrimidine-Ring Substituents Identifies Potent Plasmodium falciparum Dihydroorotate Dehydrogenase Inhibitors with Clinical Candidate Potential

22 Jun 2011

Jose M. Coteron, María Marco, Jorge Esquivias, Xiaoyi Deng, Karen L. White, John White, Maria Koltun, Farah El Mazouni, Sreekanth Kokkonda, Kasiram Katneni, Ravi Bhamidipati, David M. Shackleford, Iñigo Angulo-Barturen, Santiago B. Ferrer, María Belén Jiménez-Díaz, Francisco-Javier Gamo, Elizabeth J. Goldsmith, William N. Charman, Ian Bathurst, David Floyd, David Matthews, Jeremy N. Burrows, Pradipsinh K. Rathod, Susan A. Charman, and Margaret A. Phillips

Journal of Medicinal Chemistry
DOI: 10.1021/jm200592f

Abstract

Drug therapy is the mainstay of antimalarial therapy, yet current drugs are threatened by the development of resistance. In an effort to identify new potential antimalarials, we have undertaken a lead optimization program around our previously identified triazolopyrimidine-based series of Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) inhibitors. The X-ray structure of PfDHODH was used to inform the medicinal chemistry program allowing the identification of a potent and selective inhibitor (DSM265) that acts through DHODH inhibition to kill both sensitive and drug resistant strains of the parasite. This compound has similar potency to chloroquine in the humanized SCID mouse P. falciparum model, can be synthesized by a simple route, and rodent pharmacokinetic studies demonstrated it has excellent oral bioavailability, a long half-life and low clearance. These studies have identified the first candidate in the triazolopyrimidine series to meet previously established progression criteria for efficacy and ADME properties, justifying further development of this compound toward clinical candidate status.

Read the full article on the ACS Publications website.