Y. Yamakoshi (ETH Zuerich), E. G. V. Tiu (ETH Zürich), and S. Aroua (ETH Zürich)
Fullerene-based water-soluble materials have been considered as seed compounds for photosensitizers in photodynamic therapy (PDT) and contract reagents in magnetic resonance imaging
1 (MRI). We have been working on the development of new biocompatible fullerene (C
60, C
70 and Gd
3N@C
802) materials by complexation with or by covalent attachment of water-soluble polymers such as poly(vinylpyrrolidone) (PVP) and polyethylene glycol (PEG). Initial studies on the C
60/ or C
70/PVP complex provided sufficient water-solubility and efficient generation of superoxide (O
2•
–).
3 But a subsequent study on C
60-PVP or C
70-PVP copolymers (uncontrolled) resulted in slightly better water-solubility provided and improved generation of
1O
2. It appears that bioactivity of the C
60 or C
70 is different due to the formation of water-soluble materials in aqueous medias. In this study, we discuss on the effect of derivatization of fullerene cores on the bioactivities including reactive oxygen species generation from bis-, tris-adducts of C
60 and M
3N@C
80 (Figure) and well-defined fullerene-PVP copolymers that we have recently prepared
5 using Prato reactions.
6(1) Zhang, J. F.; Fatouros, P. P.; Shu, C. Y.; Reid, J.; Owens, L. S.; Cai, T.; Gibson, H. W.; Long, G. L.; Corwin, F. D.; Chen, Z. J.; Dorn, H. C. Bioconjugate Chem. 2010, 21, 610.
(2) Stevenson, S.; Rice, G.; Glass, T.; Harich, K.; Cromer, F.; Jordan, M. R.; Craft, J.; Hadju, E.; Bible, R.; Olmstead, M. M.; Maitra, K.; Fisher, A. J.; Balch, A. L.; Dorn, H. C. Nature 1999, 401, 55.
(3) Yamakoshi, Y.; Umezawa, N.; Ryu, A.; Arakane, K.; Miyata, N.; Goda, Y.; Masumizu, T.; Nagano, T. J. Am. Chem. Soc. 2003, 125, 12803.
(4) Oriana, S.; Aroua, S.; Söllner, J. O. B.; Ma, X.; Iwamoto, Y.; Yamakoshi, Y. Chem. Comm. 2013, 49, 9302.
(5) a) Aroua, S.; Schweizer, W. B.; Yamakoshi, Y. Org. Lett. 2014, 16, 1688-1691. b) Aroua, S.; Garcia-Borràs, M.; Bölter M. F.;, Osuna, S.; Yamakoshi, Y. J. Am. Chem. Soc. 2015, 137, 58-61. c) Aroua, S.; Tiu, E. G. V.; Ayer, M.; Ishikawa, T.; Yamakoshi, Y. Polymer Chem. 2015, 6, 2616–2619.
(6) Maggini, M.; Scorrano, G.; Prato, M. J. Am. Chem. Soc. 1993, 115, 9798.
