Synthesis and biological activity of a focused library of mitogen-activated protein kinase phosphatase inhibitors.

Mitogen-activated protein kinase phosphatase 1 is a tyrosine phosphatase superfamily member that dephosphorylates and inactivates mitogen-activated protein kinase substrates, such as p38, c-Jun-N-terminal kinase, and extracellular signal-related kinase. These mitogen-activated protein kinase substrates regulate many cellular processes associated with human diseases. In spite of this potential as a molecular target for chemotherapy, however, pharmacologically tractable inhibitors of mitogen-activated protein kinase phosphatase-1 have yet to be developed. Based on the results from a high-throughput screen for small molecule inhibitors of mitogen-activated protein kinase phosphatase-1, we designed, synthesized, and evaluated a focused library in an effort to further understand the structural requirements for mitogen-activated protein kinase phosphatase-1 inhibitory activity.