The compound [3,3,3-(CO) 3 -closo-Re(8-O(CH 2 ) 2 OCH 2 CH 2 -3,1,2-C 2 B 9 H 10 )] has been synthesized and used as precursor to several nitrosyl rhenacarborane complexes with boronbound B-O(CH 2 ) 2 O(CH 2 ) 2 -tethers to halo, amino and hydroxo functional groups. The last two in particular have afforded a pair of rhenacarborane derivatives, [3,3-(CO) 2 -3-NO-closo-Re(8-O(CH 2 ) 2 O(CH 2 ) 2 NH 3 -3,1,2-C 2 B 9 H 10 )]BF 4 and [3,3-(CO) 2 -3-NO-closo-Re(8-O(CH 2 ) 2 O(CH 2 ) 2 OH-3,1,2-C 2 B 9 H 10 )], for potential use as drug-delivery vehicles. Bioconjugates tethering our delivery vehicles to amino acids or small peptides that are not readily transported across the blood-brain barrier, either by means of membrane-based transport mechanisms or through passive diffusion, could make potential pharmacological agents for central nervous system infiltration. The final nitrosyl complexes are made following nucleophilic ring opening of the β-boron-bound 1,4-dioxane moiety and our work has established that even with unprotected hydroxo and amino terminal groups, the metal can be selectively nitrosylated using [NO] [BF 4 ] without destroying the integrity of the B-O(CH 2 ) 2 O(CH 2 ) 2 X (X = OH, NH 3 ) tether.

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