Magnesium salts/complexes of compounds useful for inhibiting the ADAM-IO protein and methods of making and purifying them are provided. Further provided are compositions comprising magnesium salts/complexes of the compounds in combination with a pharmaceutically acceptable carrier. The compounds well as such compositions comprising them are useful for the treatment of cancer, arthritis, diseases related to angiogenesis, such as renal diseases, heart diseases, such as heart failure, atherosclerosis, and stroke, inflammation, ulcer, infertility, scleroderma, endometriosis, mesothelioma, and diabetes. In addition, methods of treating forms of cancer, arthritis, and diseases related to angiogenesis in which ADAM-10 plays a critical role are provided.
