4GK4:
reference: Optimization of Inhibitors of the Tyrosine Kinase EphB4. 2. Cellular Potency Improvement and Binding Mode Validation by X-ray Crystallography., Lafleur K, Dong J, Huang D, Caflisch A, Nevado C, J Med Chem. 2013 Jan 10;56(1):84-96. doi: 10.1021/jm301187e. Epub 2012 Dec 19. PMID: 23253074

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