Disclosed herein are compounds that selectively inhibit members of the PTP family of enzymes. Synthesized compounds demonstrated selective inhibition of TC-PTP. Also provided are methods of using the compounds and formulations containing the compounds. Also described is a fluorescence-tagged combinatorial library synthesis and screening method. And methods of using these compounds to effect enzyme activity both in cells and in vitro as well as method of using these compounds to treat diseases in human and animals.