LY2784544 is a potent, selective and ATP-competitive JAK2 inhibitor (IC50 = 3 nM). effective in JAK2V617F, 8- and 20-fold selective versus JAK1 and JAK3. LY2784544 effectively inhibits JAK2V617F-driven signaling and cell proliferation in Ba/F3 cells (IC50= 20 and 55?nM, respectively). In comparison, LY2784544 is much less potent at inhibiting interleukin-3-stimulated wild-type JAK2-mediated signaling and cell proliferation (IC50 = 1183 and 1309?nM, respectively). MW: 469.94. Purity ≥98%