Synthesis of a potential boron neutron capture therapy agent: 1-aminocyclobutane-1-carboxylic acid bearing a butylboronic acid side chain

A novel boronated aminocyclobutanecarboxylic acid was synthesized for potential use in neutron capture therapy. The synthesis involves the preparation of tosylate 5, which was then converted to an amino acid using Bucherer-Strecker methodology. The molecule was modeled after the unnatural amino acid, 1-aminocyclobutane-1-carboxylic acid, which has shown high uptake in brain tumors.