Amino Jung method

A combination of the liquid-phase method and the polymer reagent technique has been applied for the synthesis of peptides by Jung et al. 216,217). In this method the soluble, polyethyleneglycol esters of the C-terminal amino acids are treated with excess of active esters covalently bound to insoluble, cross-linked polystyrene beads. After the completion of the coupling step, the excess reagent is removed by a simple filtration step instead of precipitating the PEG-peptide as in the liquid phase method (scheme 10). 

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