Preparation Of A Novel Polypeptoids Containing Sulfonium Ions By Using Ethylthionalcohol Modified Poly (N-allyl Glycine)

Polypeptoids,also known as nitrogen-substituted polyglycines,are a class of polymers with a structure similar to that of polypeptides.In the polypeptide molecule,the hydrogen on theα-carbon of the main chain is replaced by a side chain group.In the Polypeptoids structure,the side chain group replaces the hydrogen on the nitrogen atom of the amide bond of the main chain,eliminating the hydrogen bond donor,so there is no intramolecular/molecule inherent in the polypeptide in the main chain structure of the Polypeptoids polymer Inter-hydrogen bond interactions and chiral centers,and are not easily enzymatically hydrolyzed.polypeptoids have many excellent physical and chemical properties that are different from polypeptides.They have good biocompatibility and biological activity,as well as good solubility and processing properties of traditional polymer materials.They are a very promising class of biopolymers,which has received more and more attention.The main properties of polypeptoids are regulated by the side groups,and the polymers have unique physical and chemical properties through the design of the side groups.1.In this paper,a series of polypeptoids with different degrees of polymerization were synthesized through different initiator/NCA ratios,and then a series of sulfonium-containing positive ion polypeptoids were synthesized by post-modification with ethanethiol and different epoxides.It was found that the functional modification of poly（S-（3-chloro-2-hydroxypropyl）-N-（3-ethylthiopropyl）glycine sulfonium formate）can reach 100%,while being modified by other epoxides the functionalization of the polypeptoids did not reach 100%.Through research,it was found that the obtained functionalized polypeptoids showed a positive charge over the entire pH range.Moreover,poly（S-（3-（benzyloxy）-2-hydroxypropyl）-N-（3-ethylthiopropyl）glycine sulfonium formate）has a hydrophilic and hydrophobic portion of benzene group form vesicle nanostructures in water.Preliminary antibacterial studies have shown that due to the presence of sulfur ions,vesicles have a rapid killing effect on bacteria.2.Studies on amphoteric materials based on mercaptopropionic acid modified Polypeptoids:A series of Polypeptoids with different degrees of polymerization were prepared by ring-opening polymerization initiated by an initiator（benzylamine,mPEG-NH₂）,modified with thioglycolic acid and epoxides to obtain a series of zwitterion Polypeptoids.After adjusting the pH value,it was found that the oligo（ethylene glycol）（OEG）modified material exhibited LCST behavior.The oligo（ethylene glycol）（OEG₃）modified functionalized Polypeptoids had good temperature sensitivity.It exhibited a good reversible phase transition at different pH values,and its temperature range Smaller,which makes the temperature-sensitive materials of functionalized polypeptoids have great research value in the field of biomedicine.