4F4P:
reference: Highly potent aminopyridines as Syk kinase inhibitors., Castillo M, Forns P, Erra M, Mir M, Lopez M, Maldonado M, Orellana A, Carreno C, Ramis I, Miralpeix M, Vidal B, Bioorg Med Chem Lett. 2012 Sep 1;22(17):5419-23. doi: 10.1016/j.bmcl.2012.07.045., Epub 2012 Jul 20. PMID: 22877633

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