硫化氢光声探针的设计及其构效关系

Rational Design and Structure-Activity Relationship of Hydrogen Sulfide Photoacoustic Probe

分子探针的光谱性质与其本身的化学结构紧密相关,研究分子结构与光谱性能之间的关系对于理性设计性能优异的分子探针具有重要的指导意义。本工作以不对称氯代氟硼二吡咯染料为母体,通过Knoevenagel反应引入了以喹啉盐为母体结构的吸电子基团,仅改变同一位置的不同取代基,分别设计合成了四个硫化氢分子探针(BOD-NO_(2),BOD-H,BOD-BOC和BOD-NH_(2)),并对取代基变化产生的性能差异进行了系统的探究。结果表明:由于不同喹啉盐取代基电子效应的变化,影响了其吸电子能力,从而引起探针与硫化氢反应性能的变化。这四个探针均能特异性检测硫化氢,而且随着取代基吸电子能力的增强,探针与硫化氢发生亲核取代反应的速率及程度增大,吸收光谱红移量增加,光声成像效果更加优异。通过对探针构效关系的研究,成功筛选出性能优良的光声探针BOD-NO_(2),该探针能与硫化氢特异性响应,且响应速度快,选择性高,具有体内光声成像的应用潜力。本研究为硫化氢光声探针的设计提供了一种思路。

The spectral properties of molecular probes are closely related to their chemical structures.Therefore,the study of the relationship between molecule structure and its spectral properties cannot be ignore for rationally designing molecular probes with excellent performance.In this paper,the asymmetric chlorofluoroboron dipyrrole dye was used as the matrix,and the electron-absorbing group with quinoline salt as the matrix structure was introduced through the Knoevenagel reaction.Only different substituents at the same position were changed.Four hydrogen sulfide molecular probes(BOD-NO_(2),BOD-H,BOD-BOC and BOD-NH_(2))were designed and synthesized to investigate systematically the performance differences caused by the change of substituents.The results proved that the accompanying change of the different quinoline salt was the different electron withdrawing ability of probe,which leaded to the change of the reaction performance of the probe with H_(2)S.These four probes showed specifical responsiveness to H_(2)S.With the enhancement of the electron absorption ability of the substituents,the rate and extent of nucleophilic substitution reaction between the probes and H_(2)S increased,meanwhile the absorption spectrum red-shifted and the photoacoustic imaging effect was better.Finally,the probe BOD-NO_(2) with excellent photoacoustic performance was successfully screened out through the investigation of the probe structure-activity relationship,which responded specifically to H_(2)S with fast response and high selectivity.This study provides a novel idea for the design of photoacoustic probes targeting H_(2)S.