Use of N,O-bis-Fmoc-D-Tyr-ONSu for introduction of an oxidative iodination site into cholecystokinin family peptides

Int J Pept Protein Res. 1988 May;31(5):429-34. doi: 10.1111/j.1399-3011.1988.tb00899.x.


We report the synthesis of a new reagent for the introduction of an oxidative iodination site into the amino terminus of acid-labile peptides, and the use of this reagent to synthesize a novel affinity-labeling probe for the cholecystokinin (CCK) receptor. The acylation reagent, N,O-bis-fluorenylmethyloxycarbonyl-D-tyrosine hydroxysuccinimide ester, utilizes base-labile protection of both the alpha amino group and the aromatic ring hydroxyl. This can be safely removed to expose a cross-linkable free amino group on the aminopeptidase-resistant D-enantiomer of tyrosine. The synthetic probe, D-Tyr-Gly-Asp-Tyr(OSO3H)-Nle-Gly-Trp-Nle-Asp-Phe-NH2, was fully biologically active, could be radioiodinated to high-specific radioactivity (2000 Ci/mmol), bound with high affinity to the pancreatic CCK receptor, and covalently labeled the hormone-binding site. This reagent should be useful for the synthesis of a wide variety of analogues of CCK and other acid-labile peptides.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Affinity Labels / chemical synthesis*
  • Cholecystokinin / analogs & derivatives*
  • Cholecystokinin / chemical synthesis*
  • Indicators and Reagents
  • Iodine Radioisotopes
  • Mass Spectrometry
  • Oxidation-Reduction
  • Structure-Activity Relationship
  • Succinimides
  • Tyrosine / analogs & derivatives


  • Affinity Labels
  • Indicators and Reagents
  • Iodine Radioisotopes
  • Succinimides
  • N,O-bis(fluorenylmethyloxycarbonyl)tyrosine hydroxysuccinimide ester
  • Tyrosine
  • Cholecystokinin