Synthesis of novel biotin-based carborane amides

A series of novel derivatives of d -biotin containing closo - and nido -carborane residues bound to the biotin carbonyl group either directly or via a linker were synthesized. The possibility of synthesizing a d -biotin conjugate containing two closo -carborane moieties and a glutamic acid residue was shown. The obtained compounds are of interest for biological testing as potential boron delivery agents for the boron neutron capture therapy of tumors.