GSK-2830371 is a potent and selective allosteric inhibitor of Wip1 phosphatase (IC50 = 6 nM). GSK-2830371 exhibits selectivity for Wip1 over 21 other phosphatases. Increases phosphorylation of Wip1 substrates, including p53, Chk2, H2AX and ATM. Attenuates tumor cell growth in a variety of lymphoid cell lines. Also, GSK-2830371 inhibits lymphoma xenograft growth in vivo.