Synthesis of a Boronated Derivative of Gd-Texaphyrine for Potential Use in Boron Neutron Capture Therapy (BNCT)

In the last two decades treatment of brain tumors using BNCT has been performed using improved boron compounds and neutron irradiation techniques. Compounds that make use of carborane clusters, which have a high inherent boron content, should be more effective, provided, of course, the efficient and selective uptake of the boron-containing carrier molecules by cancer or other target cells. Examples of carborane cluster are the icosahedral C2B10H12 carboranes. Many porphyrins and porphyrinoid compounds have demonstrated an ability to selectively accumulate in tumors, and have therefore been considered as the possible candidates for delivery of boron to malignant tissue. The texaphyrins are aromatic pentadentate macro cyclic expanded porphyrins, which have been found to be useful as MRI contrast agents, as radiation sensitizers and in photodynamic theraphy (PDT). In this study, a new boronated texaphyrine for potential use in BNCT has been proposed and synthesized.