Incomplete TFA deprotection of N-terminal trityl-asparagine residue in fmoc solid-phase peptide chemistry

Pept Res. 1992 May-Jun;5(3):145-7.

Abstract

We demonstrate that TFA deprotection of trityl-protected N-terminal asparagine is incomplete under normal conditions, resulting in low yields or impure products. This phenomenon does not occur if the asparagine is internal, nor for trityl-protected N-terminal glutamine. Studies on the deprotection of H Asn(Trt)OH show that the incomplete deprotection is due to the extremely slow removal of a trityl group close to an amino group. The use of the new methyl-trityl protecting group overcomes this problem resulting in rapid and complete deprotection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / chemistry
  • Amino Acid Sequence
  • Amino Acids / chemistry
  • Asparagine / chemistry*
  • Chromatography, High Pressure Liquid
  • Fluorenes / chemistry
  • Molecular Sequence Data
  • Nitrogen / chemistry
  • Peptides / chemistry*
  • Trifluoroacetic Acid / chemistry*

Substances

  • Amines
  • Amino Acids
  • Fluorenes
  • N(alpha)-fluorenylmethyloxycarbonylamino acids
  • Peptides
  • Asparagine
  • Trifluoroacetic Acid
  • Nitrogen