Pyrenesulfonamide-based Sensors Bearing(CH)~+ Donor For Fluorescence Recognition Of Anions

Fluorescent chemical sensors have become a research hotspot in the field of supramolecular technology due to their advantages of simplicity,rapidity,high sensitivity,and good selectivity.As the anion plays a key role in living organisms and the environment,anion-recognition fluorescent chemical sensors have attracted more and more interest.In this dissertation,a series of（CH）⁺anion recognition sites triazolium/imidazolium derivatives were synthesized by the sulfonamide fluorophore.The receptor anion was studied in detail by means of fluorescence emission spectroscopy,ultraviolet absorption spectroscopy and ¹H NMR.Sensing and identification capabilities are as follows:1.Synthesis of one triazolium sulfonamide fluorescent receptors Py1.In the CH₃CN-H₂O（9:1,V/V）solution,Py1 has a very good fluorescence quenching response to F^-,with a detection limit as low as 39nM.¹H NMR titration and DFT calculation showed that F^-and Py1 triazole（CH）⁺,sulfonamide NH,and thiol CH formed multiple hydrogen bonds,resulting in a stable 1:1 complex.At the same time,Py1 was successfully applied to the detection of solid F^-.2.Two bis-imidazolium sulfonamide receptors Py2 and Py3 were obtained by adjusting the spacer length.Among them,the methylene-containing receptor molecule Py2 has a good fluorescence quenching response to the polyphosphates ATP,PPi,and GTP,while the propyl-containing spacer-receptor Py3 has little ability to recognize.The ¹H NMR titration indicated that the imidazolium（CH）⁺and sulfonamide NH in the acceptor molecule participate in the guest hydrogen bonding.At the same time,Py2 was successfully used for the monitoring of intracellular ATP hydrolase in HepG-2 hepatoma cells.3.Synthesis of a C16 alkyl azlactone sulfonamide receptor Py4 and its reference Py5.The receptor molecule Py4 has a very good fluorescence-enhanced response to ATP molecules in neutral aqueous solutions,whereas no long-chain-chain reference Py5 has no fluorescence response.Dynamic Light Scattering（DLS）and Tyndall effect studies have shown that Py4 can assemble into nano-particles in aqueous solution,and that the focus is enhanced with the addition of ATP.Significantly changes the photophysical properties of the probe.The probe Py4 exhibits high sensitivity and selectivity for ATP,and its detection line is also low.