Separation Of Seven-membered/fourteen-membered Cucurbitacin And Study Of Host-guest Interactions With Organic Small Molecule

This paper obtained a series of cucurbit[n]uril compounds and organic small molecules by synthesis and separation methods,including heptameric cucurbituril,helical tetradecameric cucurbit[n]uril,triphenylamine derivatives（TPABr,TPAP,TPAPy）.Then,using cucurbiturils as hosts,three different host-guest assemblies were constructed,and two host-guest crystals of heptameric cucurbituril were successfully cultivated and their host-guest properties were studied.In addition,using the rare helical tetradecameric cucurbituril and the synthesized guest,a supramolecular assembly was constructed and used as a probe to detect Fe（CN）₆^3-in solution and living kidney cells.The research content of this paper can be divided into the following three parts:Synthesized a heptameric cucurbituril with good water solubility and assembled it with N,N-dimethylaminobenzophenone（DAPE）,a guest molecule.The structure of the assembly crystal was determined by X-ray single crystal diffraction.The host-guest properties were studied by fluorescence spectroscopy,UV-visible absorption spectroscopy,nuclear magnetic titration,ITC technology and other methods.This work provides a new idea for using cucurbiturils as DAPE drug carriers.Determined the structure of the assembly crystal of heptameric cucurbituril and2,2-dihydroxypropionic acid（DMPA）by X-ray single crystal diffraction.It was found that Q[7]and DMPA formed a 1:1 host-guest complex Q[7]@DMPA.Then,the host-guest properties were studied by nuclear magnetic titration,ITC technology and other methods.This work shows that using heptameric cucurbituril with good water solubility as a drug carrier opens up a new way.Synthesized a fluorescent molecule 4,4,4-（nitrotriphenyl-4,1-diyl）tris（1-butylpyridinium-1-yl）（TPAPy）and studied its host-guest interaction with tetradecameric cucurbituril（t Q[14]）using nuclear magnetic resonance,fluorescence spectroscopy,UV-visible absorption spectroscopy,ITC and other methods.It was found that TPAPy and t Q[14]formed a 1:3 supramolecular complex TPAPy@t Q[14]by host-guest assembly.Due to the hydrophobic cavity of t Q[14]restricting the intramolecular rotation of TPAPy,it caused the AIE effect and gave it excellent fluorescence performance.This paper also found that TPAPy@t Q[14]can be used as a probe to specifically recognize Fe（CN）63-,and calculated a good detection limit.Further,this paper used it to detect Fe（CN）63-in kidney cells HK-2,and could distinguish normal cells from abnormal cells with excess Fe（CN）63-.This study not only expands the application of supramolecular probes based on rare macrocyclic structures（t Q[14]）in biological detection,but also provides a new detection method for early clinical identification of acute kidney injury（AKI）.