MRI image enhancement of bone and related tissue using complexes of paramagnetic cations and polyphosphonated ligands

摘要

Polyphosphonate ligands containing three or more phosphonate groups, combined with paramagnetic metal cations and administered in the form of pharmacologically acceptable salts, are useful as MRI contrast enhancement agents, which tend to localize in bone tissue without being conjugated to bone-specific biomolecules. Triazacyclononanes and tetraazacyclododecanes, with dihydroxyphosphorylmethyl or dihydroxyphosphorylethyl groups, optionally substituted at the methyl or ethyl bridges with alkyl, aryl, hydroxyl or amino groups, are particularly preferred.