Construct Of Pyridine-modified And Amino-modified Near-infrared Aza-bodipy

Fluorescent dyes have attracted attentions of more and more people,because of their important application in the area of biomolecule detection,tissue staining and Photo Dynamic Therapy(PDT).Boron-dipyrromethene has become a hot area of research,because of their high fluorescent yield,high molar-extinction coefficient,narrow fluorescent full width at half maximum and so on.Due to high ability of penetration,low damage of cells and low interference effect from auto fluorescence of tissue,near-infrared(NIR)dyes also have become a hot area of research.In order to get longer wavelength of maximum absorption and emission,the hydrogens in 1,3,5,7 position of BODIPY are usually substituted by aromatic rings.But at the same time this method causes poor water solubility of BDOIPY,limiting their application in biological area.Therefore,it is an urgency to modify BDOIPY to improve their solubility and the methods for this modification are PEG-modification,anionic-modification and cationic-modification.Due to the simple syntheses and the potential localization of mitochondrion,cationic-modification of BDOIPY has attracted attentions of more and more people.The key intermediates for this modification are pyridyl-modified and amino-modified BODIPY.Based on the past research of our group and the literature investigation,we are interested in the modification of Aza-BODIPY with pyridyl and amino groups and the change of photo physical properties of BODIPY,and supply innovative platform for the soluble-modification of BDOIPY.In the second chapter,we designed and synthesized a series of pyridyl-modified Aza-BODIPY dyes.Syntheses of pyridyl-modified pyrroles are the necessary steps for the syntheses of those Aza-BODIPY.We discovered an innovated “one pot” method for synthesis of pyridyl-modified pyrroles through the literature investigation and continuous experiments and synthesized nine pyridyl-modified pyrroles by this method at the first time.We synthesized nineteen asymmetric and symmetric pyridyl-modified Aza-BODIPY by using pyridyl-modified pyrroles and two phenyl substituted pyrroles as raw materials,researched their spectroscopic properties and supplied innovative platform for the soluble-modification of BDOIPY.In comparison to phenyl substituted Aza-BDOIPY,the modifications of pyridine decrease the molar-extinction coefficient and fluorescent quantum yield of Aza-BODIPY,but give rise to the bathochromic shift of the maximum absorption and emission wavelength and almost have no effect on the full width at half maximum and Stokes shift.The relative positions of nitrogen atoms have effect on the maximum absorption and emission wavelength and fluorescent quantum yield of Aza-BODIPY.In comparison to the modifications of single pyridine,the modifications of double pyridines decrease the molar-extinction coefficient and fluorescent quantum yield of Aza-BODIPYIntroduction of amino groups and then quaternary ammonium salts is another method to improve the solubility of Aza-BODIPY.In the third chapter,we designed and synthesized a series of amino-modified Aza-BODIPY dyes,supplied innovative platform for the soluble-modification of BDOIPY and researched their spectroscopic properties.We found that the modifications of amino groups decrease molar-extinction coefficient of Aza-BODIPY,but their other spectroscopic properties remain unchanged.