4R3M:
reference: Multi-substituted 8-aminoimidazo[1,2-a]pyrazines by Groebke-Blackburn-Bienayme reaction and their Hsp90 inhibitory activity., Ren J, Yang M, Liu H, Cao D, Chen D, Li J, Tang L, He J, Chen YL, Geng M, Xiong B, Shen J, Org Biomol Chem. 2015 Feb 7;13(5):1531-5. doi: 10.1039/c4ob01865f. PMID: 25490978

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