Synthesis of Cationic Dumbbell-shaped Fullerene Nanostructures as Potential Photodynamic Sensitizers

Abstract

A design of novel hydrophilic tetracationic dumbbell-shaped [60]fullerene nanostructures was made by balancing the hydrophilicity and hydrophobicity characteristics of the fullerene adduct for their potential application as photodynamic sensitizers in the PDT treatment. A sequential protection-deprotection reaction pathway was applied for the functional differentiation between primary and secondary amine moieties of pentaethylene hexamine. Synthesis of the target molecule involves two key steps of unsymmetrical esterification and amidation of malonic acid and subsequent fullerenation. The synthetic strategy was accomplished using mild reaction conditions in the intermediate molecule preparation and led a moderate overall product yield.

Keywords:

• Tetracationic fullerene derivatives
• dumbbell-shaped nanostructures
• photosensitizer
• photodynamic therapy
• amphiphilic fullerenes

Acknowledgements

We thank the National Institute of Health for financial support under the grant number 1R01CA137108 and the Air Force Office of Scientific Research under the grant numbers FA9550-09-1-0380.