Oligomeric carboranes

The arylene-ether-arylene-ketone or siloxy links between carborane ico-sahedra in the polymers just discussed play an important role in rendering these polymeric molecules flexible enough to allow their dissolution in selected solvents and in generally making these materials tractable. Oligomeric carborane systems have been prepared in which a few para-carborane icosahedra are directly linked to each other, but even short chains containing but four... 

Hawthorne and co-workers have reported the selective uptake of homogeneous flourescein-labeled nzYfo-carboranyl oligomeric phosphate diesters nido-OPDs) by cell nuclei within 2h after microinjection. The location in the cell of nido-OPDs uptake was found to depend on the location of the carboranyl moiety in the nido-OPDs. When the carborane cage was located on a side chain attached to the oligomeric... 

Oligonucleotides bearing nido-carborane have been synthesized as phospho-diesters using an automated DNA synthesizer (see Scheme 2.2-14) [39]. These oligophosphates are homogeneous, very hydrophilic and are readily taken up into cells. Fluorescein-labeled nido-carboranyl oligomeric phosphate diesters accumulate in the cell nucleus [40]. 

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