Relative to other polycyclic frameworks (1–3), a carborane cage (4 and Cs·5) exerts a significant biological effect as an inhibitor of the purinergic P2X₇ receptor (P2X₇R) which allows one to target depression in vivo and thus demonstrate, for the first time, that a carborane has the capacity to modify CNS activity.

Combining therapeutic and diagnostic tools into a single ‘theranostic’ platform lies at the forefront of cancer research. Some of the most promising theranostics exploit the unique nuclear and electronic properties of the lanthanoid metal gadolinium.

Carboranes are an important class of electron-delocalized icosahedral carbon-boron clusters with unique physical and chemical properties, which can offer various functions to polymers including enhanced heat-resistance, tuned electronic properties and hydrophobicity, special ability of dihydrogen bond formation, and thermal neutron capture. Carborane-containing polymers have been synthesized mainly by means of step-growth polymerizations of disubstituted carborane monomers, with chain-growth polymerizations of monosubstituted carborane monomers including ATRP, RAFT, and ROMP only utilized recently. Carborane-containing polymers may find application as harsh-environment resistant materials, ceramic precursors, fluorescent materials with tuned emissive properties, novel optoelectronic devices, potential BNCT agents, and drug carriers with low cytotoxicity. This review highlights carborane-containing polymer synthesis strategies and potential applications, showcasing the versatile properties and possibilities that this unique family of boron compounds can provide to the polymeric systems.

The unique chemistry of boron allows for the utilisation of novel building-blocks which are not traditionally found in medicinal chemistry. The pharmaceutical industry has begun to exploit boronic acid derivatives as new drugs and several research groups are also exploring 1,2-azaborines and icosahedral boranes known as carboranes as boron-based structural motifs, with great promise for innovative drug design. Recent advances in the medicinal chemistry of these three important boron moieties are highlighted and illustrated with selected examples.