Recognition Of Tetrahedral Anions By Water-Soluble Oligourea-Based Receptors

Anion recognition based on the role of host and guest as an important branch of supramolecular chemistry has made great progress in recent years and is one of the important directions for the future development of supramolecular chemistry.Anions are very important in biology,environment and nature.The tetrahedral anions include phosphate,sulfate,thiosulfate,etc.,especially the transport of phosphate anions in transmembrane transport,energy conversion,genetic information transfer,supramolecular Catalysis,mass analysis and detection are of great significance.The selective identification of such anions has great application prospects in drug design and preparation,environmental detection and treatment,but it is still a challenging problem.The strong hydration energy of phosphate is difficult to identify in water.In the traditional anion recognition study,the electrostatic-based receptors,although solving the problem of ligand water solubility,are difficult to achieve high-selectivity recognition due to the lack of directionality of electrostatic interaction;on the other hand,hydrogen-bonded receptors Despite its high selectivity,poor water solubility has been the main reason for limiting its further development.In addition,this kind of research usually uses an organic solvent as an action system,and it is impossible to realize an inorganic anion such as sulfate or thiosulfate which is common in water and adenosine phosphate which plays an important role in living organisms.The first chapter introduces the research status of tetrahedral anion recognition,enumerates the typical representatives of various tetrahedral anion receptors,analyzes the defects of several receptor studies,and presents the challenges of phase anion recognition research.As a group with high selectivity,urea receptors have been widely used in anion coordination studies.By functionalization,polyurea receptors are dissolved in polar solvents,especially aqueous solutions,to achieve selective recognition of common tetrahedral anions such as phosphates and sulfates.At the same time,by imitating the human environment,the direct energy sources ATP,ADP,and AMP in the organism are identified,and the subject-guest recognition research is extended from inorganic anions to organic anions.This work is of great significance for related research in the environmental and biological fields.In the second chapter,we designed a triurea receptor that can have a certain solubility in aqueous solution,imitating the environment of the organism,and identifying and studying common tetrahedral anions and adenosine phosphates.A positively charged polyurea receptor is obtained by methylating the amine.On the one hand,the charge of the ammonium ions causes the ligand to dissolve in a polar solvent,especially an aqueous solution,which can simulate the solution environment of the organism,and at the same time,the Coulomb force interacts with the anion to greatly improve the binding force.On the other hand,the polyurea group provides a hydrogen bond,and the hydrogen bond has a certain directionality,so that the binding of the acceptor to the anion proceeds,and the tetrahedral anion has high selectivity.In addition,by identifying the adenosine,an important energy substance in the living body,the recognition of anions achieves a leap from inorganic phosphate to organic phosphate.