4JLS:
reference: Inhibition of the Escherichia coli 6-oxopurine phosphoribosyltransferases by nucleoside phosphonates: potential for new antibacterial agents., Keough DT, Hockova D, Rejman D, Spacek P, Vrbkova S, Krecmerova M, Eng WS, Jans H, West NP, Naesens LM, de Jersey J, Guddat LW, J Med Chem. 2013 Sep 12;56(17):6967-84. doi: 10.1021/jm400779n. Epub 2013 Aug 27. PMID: 23927482

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