Study On The Interaction Of Several New PPT Supramolecular Systems With BSA And DNA

20(S)-Popopanaxatriol(PPT)is a ginseng saponin,which was extracted from plants such as ginseng,American ginseng or Panax.It has good effect in regulating blood sugar,anti-aging and anti-fatigue.Especially in anti-tumor,induced tumor cell differentiation and other aspects,the effect is more significant.But given the PPT solubility concentrations are often lower than required for therapeutic purposes it,thus affecting the efficacy of the drug.Cyclodextrin(CD)and its derivatives have the unique "internal hydrophobic,outer hydrophilic" structure can embed insoluble drugs or groups into their molecular cavities in the form of covalent bonds,by their own Water-based,so that the inclusion of a good wettability,thereby enhancing the drug's water solubility and bioavailability.In recent years,cyclodextrin has become one of the hotspots in the field of supramolecular chemistry.At the same time,the study of the interaction of small molecules and proteins in the drug helps to analyze the mechanism of action from the molecular level,not only help to grasp the process of absorption,distribution and transport of small molecules in vivo,but also in protein science,Pharmacology,toxicology and pharmacokinetics and other research areas of great significance.In addition,the study of DNA and small molecules of the interaction,help from the genetic level to understand the mechanism of action of drugs and DNA to explore the pathogenesis of certain diseases,so that through molecular design to find effective therapeutic drugs.Therefore,the study on the interaction between drug molecules and proteins and DNA has been widely concerned in the fields of life sciences,medicine,chemistry.In this paper,the synthesis of several novel CD derivatives,and with PPT prepared into the supramolecular system,further study of PPT supramolecular system and BSA and DNA interaction.Specific experimental work is as follows:1.Synthesizing 8 kinds of modified ?-CDs(host 1-8),in which host 1-5,and7 were novel modified ?-CDs,and preparing 8 kinds of supramolecular systems with PPT.Then using 1H NMR,SEM,XRD,IR and other methods to characterize them.According to the 2D ROESY spectrum speculated the possible binding mode,by UV titration calculation between the host and the guest of stability constant ratio.The results show that the host and guest form a 1: 1 supramolecular system.2.The interaction between several novel PPT systems and BSA was studied by fluorescence spectroscopy.The results showed that the main forces of the binding process of PPT and BSA were hydrogen bond and van der Waals force,and the process was static quenching.Simultaneous fluorescence spectroscopy and binding distance experiments show that the supramolecular system acts on the tryptophan residues of BSA,and dipole-dipole nonradiative energy transfer can also cause fluorescence quenching of BSA.3.The interaction between several novel PPT systems and ct-DNA was studied by UV-Vis absorption spectroscopy.The results showed that novel PPT systems and ct-DNA forms a new 1: 1 complex,entropy change and enthalpy change as the driving force of their interaction.4.The interaction mechanism host of 5/PPT system,host 5/ PPT and BSA and ct-DNA was studied by theoretical simulation(molecular docking and molecular dynamics simulation).The theoretical results were in agreement with the experimental results.