N-hydroxy-2-(alkyl, aryl, or heteroaryl sulfanyl, sulfinyl, or sulfonyl)-3-substituted alkyl, aryl or heteroarylamides as matrix metalloproteinase inhibitors

Matrix metalloproteinases (MMPs) are a group of enzymes that have been implicated in the pathological destruction of connective tissue and basement membranes. These zinc containing endopeptidases consist of several subsets of enzymes including collagenases, stromelysins and gelatinases. TNF-alpha converting enzyme (TACE), a pro-inflammatory cytokine, catalyzes the formation of TNF-alpha from membrane bound TNF-alpha precursor protein. It is expected that small molecule inhibitors of MMPs and TACE therefore have the potential for treating a variety of disease states. The present invention provides low molecular weight, non-peptide inhibitors of matrix metalloproteinases (MMPs) and TNF-alpha converting enzyme (TACE) for the treatment of arthritis, tumor metastasis, tissue ulceration, abnormal wound healing, periodontal disease, bone disease, diabetes (insulin resistance) and HIV infection having the formula wherein R2 and R3 form a heterocyclic ring and A is S, S(O), or S(O)2, and R1 and R4 are defined herein.