7- (2,4-Dinitrophenoxy) -4-methyl-2H-chromen-2-one

7- (2,4-Dinitrophenoxy) -4-methyl-2H-chromen-2-one (Compound 1) serves as a fluorescent probe for detecting hydrogen sulfide (H2S) . It is characterized by a low detection limit (4x10^-6 mol/L), high selectivity, and great sensitivity. At a concentration of 150 μg/mL, it exhibits negligible cytotoxicity. The excitation wavelength is 331 nm, while in DMSO solvent, it emits at approximately 385 nm; upon addition of HS-, the fluorescence intensity significantly increases around 392 nm.