Matrix metalloproteinases functional groups

The ability of hydroxamic acids to act as bidentate ligands has made this functional group a key component in the design of most matrix metalloproteinase inhibitors. Due to its labile and diprotic nature, the hydroxamate is typically installed in its protected form at the end of the synthetic sequence. ... 

Another example related to therapeutics involves hydroxamic acids, which have been widely used as a key functional group of potential therapeutics targeting at zinc-bound matrix metalloproteinases involved in cancers [7]. But the hydroxamic acids are also iron chelators [8], and since iron is the most abundant transition metal ion present in the human body, studies are being conducted in order to find new stable conformers and tautomers of hydroxamic acids that would preferentially bind to zinc. 

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