2-溴-4'-羟基苯乙酮抑制剂PTP Inhibitor I is a cell-permeable, protein tyrosine phosphatase (PTP) inhibitor that covalently blocks the catalytic domain of the Src homology region 2 domain-containing phosphatase (SHP-1(ΔSH2)) with a Ki value of 43 µM and PTP1B with a