Novel Thienopyrimidine Inhibitors of <i>Leishmania N</i>-Myristoyltransferase with On-Target Activity in Intracellular Amastigotes
作者:Andrew S. Bell、Zhiyong Yu、Jennie A. Hutton、Megan H. Wright、James A. Brannigan、Daniel Paape、Shirley M. Roberts、Charlotte L. Sutherell、Markus Ritzefeld、Anthony J. Wilkinson、Deborah F. Smith、Robin J. Leatherbarrow、Edward W. Tate
DOI:10.1021/acs.jmedchem.0c00570
日期:2020.7.23
The leishmaniases, caused by Leishmania species of protozoan parasites, are neglected tropical diseases with millions of cases worldwide. Current therapeutic approaches are limited by toxicity, resistance, and cost. N-Myristoyltransferase (NMT), an enzyme ubiquitous and essential in all eukaryotes, has been validated via genetic and pharmacological methods as a promising anti- leishmanial target. Here we describe a comprehensive structure-activity relationship (SAR) study of a thienopyrimidine series previously identified in a high-throughput screen against Leishmania NMT, across 68 compounds in enzyme- and cell-based assay formats. Using a chemical tagging target engagement biomarker assay, we identify the first inhibitor in this series with on-target NMT activity in leishmania parasites. Furthermore, crystal structure analyses of 12 derivatives in complex with Leishmania major NMT revealed key factors important for future structure-guided optimization delivering IMP-105 (43), a compound with modest activity against Leishmania donovani intracellular amastigotes and excellent selectivity (>660-fold) for Leishmania NMT over human NMTs.