Secondary-Rim γ-Cyclodextrin Functionalization to Conjugate with C 60 : Improved Efficacy as a Photosensitizer

Chemistry. 2017 Jul 18;23(40):9462-9466. doi: 10.1002/chem.201700782. Epub 2017 Jun 29.

Abstract

DIBAL-H-mediated demethylation provides a novel method to access secondary-rim functionalized γ-cyclodextrin. 2A ,3B -Dihydroxyl-per-O-methylated-γ-cyclodextrin has been obtained, whose conjugation with C60 allows access to the most water-soluble C60 conjugate described so far. The water solubility of 0.12 m (550 mg mL-1 ) is 150 times higher than that of the native γ-CD/C60 complex. Its singlet oxygen (1 O2 ) quantum yield is 0.39, an increase of one to two orders of magnitude compared to that of α(β)CD-C60 conjugates.

Keywords: C60; aggregation; gamma-CD; photosensitizer; secondary rim.