Synthesis And Application Of Fluorescent Probes Based On Naphthone Scaffold

Small molecular substances have significant effects on cell homeostasis,signal transduction,immunity and metabolism and living environment in vivo.Hydrazine is a volatile toxic substance soluble in water,which has neurotoxic effect and causes serious damage to human organs through skin contact or oral intake.Hypochlorite is an important source of reactive oxygen species,which plays an important role in the pathophysiological process of the biological system.Too much or too low levels of hypochlorite in the human body will lead to diseases.However,the traditional detection methods for the detection of these two small molecular substances have some problems,such as expensive instrument,time-consuming,complex sample treatment,low sensitivity,poor biocompatibility,unable to realize dynamic and visual detection of small molecular substances in tissues and cells.Compared with the traditional detection and analysis technology,fluorescent probe has the advantages of small size,simple operation,non-invasive,specificity and sensitivity,and can realize real-time,dynamic and visual monitoring of small molecules in living cells and tissues.Therefore,the simple and fast fluorescence probe technology has attracted wide attention.As an important chemical raw material,tetralone is the basic structural unit of many natural products and pharmaceutical intermediates,and plays an important role in the fields of medicine,chemical industry and agriculture.In this paper,based on naphthone scaffold,two kinds of small molecular fluorescent probes were designed and synthesized for the detection of small molecular hydrazine and hypochlorite,and their spectral properties and biological applications were studied.Based on the naphthone scaffold and barbituric acid as recognition group,a small molecular fluorescent probe DPT for the detection of hydrazine was synthesized.The probe DPT itself has weak fluorescence.After adding N₂H₄·H₂O,the addition cyclization-reduction reaction of aldol with barbituric acid leads to the departure of barbituric acid,and the obtained DPT-N₂H₄ emits strong yellow fluorescence.The results show that the probe DPT has the advantages of large Stokes shift（>140 nm）,high fluorescence quantum yield,good linear relationship,high sensitivity,good selectivity,strong anti-interference ability and low detection limit（50 n M）.In addition,the probe DPT has low cytotoxicity and good biocompatibility,and was successfully applied to fluorescence imaging of N₂H₄·H₂O in living cells.Based on the naphthone scaffold,an"off-on"small molecule fluorescent probe DEI for the detection of Cl O^-was synthesized.The probe DEI has almost non-fluorescent.After reacting with Cl O^-,the intramolecular C=C bond is cut off,and the aldehyde group compound with strong fluorescence is obtained.The probe DEI has the advantages of high fluorescence quantum yield,good linear relationship,strong anti-interference ability,high sensitivity and selectivity,and its detection limit is 0.65 n M.The combination of fluorescence probe technology and confocal microscopy can improve the detection to the cellular and subcellular level,effectively realize the dynamic monitoring of small molecular substances in organisms,and provide technical means for disease diagnosis,treatment and environmental monitoring.