Synthesis And Recognition Of Fluorescent Probes Based On 2-(2'-Hydroxyphenyl)benzothiazole Derivatives

In recent years,benzothiazoles have received extensive attention in the field of fluorescent probes,because 2-?2'-hydroxyphenyl?benzothiazole derivatives have a typical excited state intramolecular proton transfer?ESIPT?characteristic structure.The benzothiazole is simple in synthesis,easy to obtain raw materials,and has good fluorescence properties,which provides a good idea for future probe design.In this paper,four fluorescent probes were designed and synthesized using benzothiazole as the precursor,and the fluorescence recognition properties of the synthesized probes were investigated.1.The probe HBTPB was synthesized.The probe HBTPB has high selectivity and high sensitivity recognition for H₂O₂,which can achieve near-infrared emission and ratio type fluorescence changes.HBTPB can detect endogenous and exogenous H₂O₂ in living cells.Cell colocalization experiments showed that the probe HBTPB can target mitochondria.2.The probe HBT-N was synthesized.The probe HBT-N exhibits near-infrared emission and high selectivity to ONOO^-in a solution of CH₃CN/H₂O?3:7,v/v,PBS 20 mM,pH=7.4?,and has a wide pH range.It was found by cell imaging experiments that the probe HBT-N can detect ONOO^-in living cells.3.The probe HBT-HB was synthesized.The probe HBT-HB has high selectivity to Cu²⁺,and the HBT-HB-Cu²⁺generated in situ quenches the fluorescence and can be used for relaying pyrophosphate?PPi?.The identification process has the advantages of high selectivity,strong anti-interference ability and fast response speed.4.The probe HBTP-NBD was synthesized.The probe HBTP-NBD has high selectivity to Hcy/Cys and can be effectively distinguished from GSH.The reaction rate is faster and the sensitivity is higher.HBTP-NBD can detect Hcy in living cells.The results of cell colocalization experiments indicate that the probe HBTP-NBD can target mitochondria.