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Solution behavior of a sugar-based carborane for boron neutron capture therapy: a nuclear magnetic resonance
Claudia Bonechi1, Sandra Ristori, Silvia Martini
1Dipartimento di Scienze e Tecnologie Chimiche e dei Biosistemi, Università di Siena, via A. Moro 2, 53100 Siena, Italy.
Abstract:
The physico-chemical properties of beta-lactosyl-closo-orthocarborane in water solution were investigated by multinuclear NMR, (13)C NMR relaxation, and ab-initio calculations. This molecule represents a potentially selective boron carrier in Boron Neutron Cancer Therapy (BNCT) and exhibits amphiphilic characteristics. Its structural and dynamic features were studied comparing NMR data acquired in both aggregating and non-aggregating conditions. Aggregates are characterized by rapid exchange with the bulk and by high sensitivity to temperature conditions. An unusually stable intra-molecular CH...O hydrogen bond was found to persist in water solution both for the free molecules and after aggregate formation. At the same time, inter-molecular specific CH()O interactions do not seem effective in the aggregate formation process, which appears to take place only on non-specific hydrophobic basis.
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