Solid-phase peptide synthesis Noncovalent protection

Noncovalent Protection in Solid-Phase Peptide Synthesis... 

The use of crown ethers for noncovalent protection of A -amino acids and for protection of side chains of Lys or Arg residues has found the most successful utility in the fragment condensation approach to solid- and solution-phase peptide synthesis (15-17). 

Solid-Phase Synthesis of Rhodamlne Labeled Peptide Nucleic Acids using Noncovalent Protection... 

Mayfield, L. D. and Corey, D. R. (1999) Enhancing solid phase synthesis by a noncovalent protection strategy-efficient coupling of rhodamine to resin-bound peptide nucleic acids. Bioorg. Med. Chem. Lett. 9,1419-1422. 

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