AbstractBoric acid, H3BO3, is a weak acid and at physiological pH is in the form of an uncharged small molecule. Behaving as a Lewis acid, it forms complexes with amino- and hydroxy acids, carbohydrates, nucleotides and vitamins through electron donor-acceptor interactions. These interactions are believed to be beneficial for human health. Synthetic bis-chelate complexes of boric acid with organic biomolecules are therefore considered for nutritional and/or pharmaceutical applications. The use of boric acid for BNCT has gained attention due to the short biological half-life, solubility, plasma circulation and the non-selective soft tissue accumulation properties of this simple molecule. Complexation of boric acid with sugars is of particular importance in understanding the role of boron as a carrier for nucleotides and carbohydrates. A potential and catalytic role of boric acid in peptide and nucleic acid synthesis and in the stabilization of sugar molecules by acting as a complexing agent have been demonstrated. Its possible role as a phosphorylation chaperone in a prebiotic world has been recently suggested. This contribution reviews the highlights in the physiologic, therapeutic and prebiotic significance of boric acid in the last decade.
Mixed ligand complex formation of FeIII with boric acid and typical N-donor multidentate ligands
