The neutrophil-derived serine proteases human leukocyte elastase (HLE) and proteinase 3 (PR3) have been implicated in various inflammatory diseases such as pulmonary emphysema, chronic bronchitis, asthma, cystic fibrosis, rheumatoid arthritis, psoriasis, and others. Poor regulation of the activity of these enzymes by their endogenous protein inhibitors is believed to result in the degradation of the major components of intracellular matrix. Agents that function as potent and selective inhibitors of these enzymes are of potential therapeutic value. The research described herein was an attempt to design and synthesize a class of non-covalent inhibitors of HLE and PR3 based on the cyclosulfamide scaffold. However during the course of these studies a new class of covalent inhibitors of HLE was discovered.