Synthesis of D2 receptor ligand analogs incorporating one dicarba-closo-dodecaborane unit

Boron clusters, and especially dicarba-closo-dodecaboranes, can be used as hydrophobic pharmacophores in the design of new drugs and radiotracers. In the current Letter, analogs of enantiomeric substituted benzamides (Raclopride and FLB-457) in which the phenyl ring has been substituted by a carborane cage (either orto- or meta-carborane) have been developed as potential D2 receptor antagonists. The formation of intramolecular hydrogen bonds (in solution) and the stability of the new chemical entities have been evaluated by means of 1H NMR and HPLC–MS, respectively.