Abstract: The present invention provides novel compounds, novel compositions, methods of their use, and methods of their manufacture, where such compounds are pharmacologically useful inhibitors of Protein Tyrosine Phosphatases (PTPase's) such as PTP1B, CD45, SHP-1, SHP-2, PTP&agr;, LAR and HePTP or the like. The compounds are useful in the treatment of type I diabetes, type II diabetes, impaired glucose tolerance, insulin resistance, obesity, immune dysfunctions including autoimmunity diseases with dysfunctions of the coagulation system, allergic diseases including asthma, osteoporosis, proliferative disorders including cancer and psoriasis, diseases with decreased or increased synthesis or effects of growth hormone, diseases with decreased or increased synthesis of hormones or cytokines that regulate the release of/or response to growth hormone, diseases of the brain including Alzheimer's disease and schizophrenia, and infectious diseases.