Fluorescent chemosensors based on spiroring-opening of xanthenes and related derivatives

Different xanthene derivatives according to their analytes with mechanistic schemes published from 1997 to February 2011 are introduced. Kim and co-workers reported the design and synthesis of a new rhodamine-based derivative, bearing an N-butyl-1,8-naphthalimide group. Huang's and Li's groups reported a rhodamine B derivative, containing a highly electron-rich S atom as a fluorescence turn-on chemodosimeter for Cu ²⁺ in an aqueous medium. Peng et al. reported a rhodamine-based chemodosimeter, via a mechanism of Hg ²⁺-promoted hydrolysis. Lin et al. presented a rhodamine-based probe, composed of a sulfur atom and an alkyne moiety for the irreversible detection of Hg ²⁺. Shang et al. synthesized molecule, composed of a fluorescein fluorophore and a rhodamine B hydrazide linked together by a thiourea spacer. Nagano and co-workers have synthesized a series of symmetric and asymmetric rhodamine derivatives,using rhodamine as scaffolds.