4RIO:
reference: Discovery of pyrrolo[1,2-b]pyridazine-3-carboxamides as Janus kinase (JAK) inhibitors., Duan JJ, Lu Z, Jiang B, Yang BV, Doweyko LM, Nirschl DS, Haque LE, Lin S, Brown G, Hynes J Jr, Tokarski JS, Sack JS, Khan J, Lippy JS, Zhang RF, Pitt S, Shen G, Pitts WJ, Carter PH, Barrish JC, Nadler SG, Salter-Cid LM, McKinnon M, Fura A, Schieven GL, Wrobleski ST, Bioorg Med Chem Lett. 2014 Dec 15;24(24):5721-6. doi: 10.1016/j.bmcl.2014.10.061., Epub 2014 Oct 24. PMID: 25453808

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