For 10 points, name these coordination compounds in which one or more polydentate ligands bind with and often sequester a central metal ion.
One group of these compounds is based on hydroxamic acid and typically consists of non-ribosomal peptides, known as siderophores.  The namesake effect of these compounds describes their increased thermodynamic stability as a result of a more positive entropy, and molecules like DMSA can be used in their namesake therapy to treat certain poison victims. Seen biologically in porphyrins and chlorophyll, a common example of these is the amino acid EDTA. For 10 points, name these coordination compounds in which one or more polydentate ligands bind with and often sequester a central metal ion.
One group of these compounds is based on hydroxamic acid and typically consists of non-ribosomal peptides, known as siderophores.  
chelates [accept chelating agent]