2AYP:
reference: Synthesis and biological evaluation of 3-ethylidene-1,3-dihydro-indol-2-ones as novel checkpoint 1 inhibitors., Lin NH, Xia P, Kovar P, Park C, Chen Z, Zhang H, Rosenberg SH, Sham HL, Bioorg Med Chem Lett. 2006 Jan 15;16(2):421-6. Epub 2005 Oct 18. PMID: 16242328

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