4FYN:
reference: Rational design of highly selective spleen tyrosine kinase inhibitors., Lucas MC, Goldstein DM, Hermann JC, Kuglstatter A, Liu W, Luk KC, Padilla F, Slade M, Villasenor AG, Wanner J, Xie W, Zhang X, Liao C, J Med Chem. 2012 Dec 13;55(23):10414-23. doi: 10.1021/jm301367c. Epub 2012 Nov, 27. PMID: 23151054

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