Skip to main content

Synthesis of disulfated peptides corresponding to the
N-terminus of chemokines receptors CXCR6 (CXCR61−20) and DARC (DARC8−42) using a
sulfate protecting group strategy

Research Authors
Ahmed M. Ali and Scott D. Taylor
Research Journal
Journal of Peptide Science
Research Publisher
NULL
Research Rank
1
Research Vol
16
Research Website
DOI 10.1002/psc.1220
Research Year
2010
Research Abstract

Tyrosine sulfation is a post translationalmodification that occurs on integral membrane and secreted proteins, and is required for mediating crucial biological processes. Until recently the synthesis of sTyr peptides, especially those containing multiple sTyr residues, were among the most challenging peptides to prepare. We recently described an efficient strategy for Fmocbased solid phase synthesis of sTyr peptides in which the sulfate group in the sTyr residue(s) is protected with a DCV group (FmocTyr(SO3DCV)OH, 1). After cleavage of the peptide from the support the DCV group is removed by hydrogenolysis. Here, we demonstrate that sTyr peptides containingMet or Trp residues can be prepared using our sulfate-protecting group strategy by preparing peptides corresponding to residues 1–20 of chemokine receptor CXCR6 and 8–42 of chemokine receptor DARC. Removing the DCV groups at the end of the syntheses was readily achieved, without any reduction of the indole ring in Trp, by performing the hydrogenolysis in the presence of triethylamine. These conditions were found to be particularly efficient for removing the DCV group and superiour to our original conditions using H2, ammonium formate, Pd/C. The presence of Met was found not to interferewith the removal of the DCV group. The use of pseudoproline dipeptides and N-backbone protection with the 2,4-dimethoxybenzyl group were found to be very effective tactics for preventing aggregation and aspartimide formation during the synthesis of thesepeptides.Wealso report an alternative andmorecost effective synthesis of amino acid 1.