Ρητίνες πολυστυρολίου - πολυαμιδίων με εφαρμογή στην πεπτιδική σύνθεση

Abstract

In the present thesis, the development and study of novel polystyrene-polyamide resins is described. Our study starts with the investigation of a general methodology of synthesis of monomers-polyethylene glycol (PEG) derivatives with their potent application in PEGylation of proteins and moreover their use as structural components of new hydrophilic resins. Utilizing one of these monomers as a repeated structural unit, a polystyrene resin with a free amino group and Fmoc-Lys(Fmoc)-OH (when branched polymers are required), we eventually prepared 18 different resins. Among these resins we selected those that combine satisfactory or good swelling in water and excellent or very good swelling in Solid Phase Peptide Synthesis solvents. Moreover, the synthesis of a model-peptide on the selected resins was studied, regarding required coupling time, excess of the added reagents and purity. Better results were obtained for H-PEG2-AM Resin (where PEG: -NΗ-CH2-(CH2CH2O)3-(CH2)3-NH-CO-CH2CH2CO- and AM: Aminomethyl). Therefore this resin was chosen to study potent applications of the recently developed polystyrene-polyamide resins. Some of these applications are the following: Peptides-enzyme substrates bound on H-PEG2-AM Resin were tested in enzymatic reactions (e.g. reactions with trypsin or matrilysin). In addition, on resin orthogonal thioester ligation reactions of peptide fragments and thioester reactions were also studied. Finally peptide segments anchored to the resin and bearing Cys with a free sulphydryl were left to react with various oxidizing reagents and their disulphide bridges formation reactions with other peptide fragments or Cys were also examined