JAK2 JH2 Fluorescence Polarization Assay and Crystal Structures for Complexes with Three Small Molecules

Abstract

A competitive fluorescence polarization (FP) assay is reported for determining binding affinities of probe molecules with the pseudokinase JAK2 JH2 allosteric site. The syntheses of the fluorescent <b>5</b> and <b>6</b> used in the assay are reported as well as <i>K</i>_d results for 10 compounds, including JNJ7706621, NVP-BSK805, and filgotinib (GLPG0634). X-ray crystal structures of JAK2 JH2 in complex with NVP-BSK805, filgotinib, and diaminopyrimidine <b>8</b> elucidate the binding poses.