1,8-Anthrancene disulfonamide: A simple but highly sensitive and selective fluorescent chemosensor for Hg2+ in aqueous media

New 1,8-anthrancene disulfonamide derivative 1 was designed and synthesized as a selective fluorescent sensor for Hg2+ over miscellaneous metal ions in aqueous media. Upon mixing with Hg2+ in DMSO:H2O (2:98, v/v), the decrease of fluorescence intensity and a bathochromic shift of absorbance of 1 could be observed. The Job plot indicated the formation of 1:1 complex between 1 and Hg2+. Background metal ions showed small or no interference with the detection of Hg2+. The binding mode and effect of N-substituent groups were also investigated.