Skeleton-selective fluorescent chemosensor based on cyclodextrin bearing a 4-amino-7-nitrobenz-2-oxa-1,3-diazole moiety

Abstract

A new type of fluorescent chemosensor, based on modified cyclodextrins bearing the fluorophore unit NBD–amine, was prepared. One of these new chemosensors, NC0βCD, is sensitive to adamantane and borneol derivatives, which have a comparatively spherical shape that fits the β-CD cavity, but is not sensitive to bile acids, which are strongly bound by the native β-CD. Even in the presence of a bile acid, NC0βCD can detect 1-adamantanol. Another of this new type of chemosensors, NC0γCD, is sensitive to bile acids but not to adamantane derivatives. The response of the new type of chemosensors to a guest was an increase in the fluorescence intensity.