Abstract
Despite correct purity of crude peptides prepared on trityl resin by Fmoc/tBu microwave assisted solid phase peptide synthesis, surprisingly, lower yields than those expected were obtained while preparing C-terminal acid peptides. This could be explained by cyclization/cleavage through diketopiperazine formation during the second amino acid deprotection and third amino acid coupling. However, we provide here evidence that this is not the case and that this yield loss was due to high temperature promoted hydrolysis of the 2-chlorotrityl ester, yielding premature cleavage of the C-terminal acid peptides.
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C. Echalier and S. Al-Halifa contributed equally to the work.
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Echalier, C., Al-Halifa, S., Kreiter, A. et al. Heating and microwave assisted SPPS of C-terminal acid peptides on trityl resin: the truth behind the yield. Amino Acids 45, 1395–1403 (2013). https://doi.org/10.1007/s00726-013-1604-z
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DOI: https://doi.org/10.1007/s00726-013-1604-z