Beryllium Complexes with Bio-Relevant Functional Groups: Coordination Geometries and Binding Affinities.

The coordination mode around beryllium in proteins and the binding affinity towards the peptide are unknown because there have been no coordination compounds of beryllium with ligands bearing bio-relevant functional groups. We report the first comprehensive study on Be complexes with monodentate carboxylic acids, esters, aldehydes, and alcohols. Through solution and solid-state techniques we determined that the binding affinities of Be2+ ions towards the functional groups are: carboxylate > alcohol > aldehyde > ester. Crystal structures of all the compounds have been determined including the unprecedented dodeca-nuclear macrocyclic ring structure of non-basic beryllium benzoate, which is the first example of those beryllium carboxylates. These findings enable the evaluation of potential beryllium binding sites inside proteins and is required to understand the mechanism of metal-triggered immune responses.