Complex Formation of p‐Boronophenylalanine With Some Monosaccharides

Abstract

To increase the solubility of p-boronophenylalanine (p-bpa) in neutral pH solution, the complex formation of p-bpa with some monosaccharides has been studied by 11B-NMR and UV spectroscopy. The complex formation constants (log K) obtained by the UV method in pH 7.4 solution are 2.43 (fructose), 2.19 (mannitol), 1.28 (galactose), 1.10 (mannose), and 0.85 (glucose), respectively. One hundred milligrams of p-bpa is able to dissolve in 3 ml of 0.3 M fructose solution at pH 7.98. Based on the results obtained, the behavior of p-bpa-monosaccharide complexes in vivo after injection of the complex solution is described.