(p-Sulfomethyl)phenylalanine as a mimic of O-sulfatyl-tyrosine in synthetic partial sequences of P-Selectin glycoprotein ligand 1 (PSGL-1)

Fmoc-l-(p-sulfomethyl)phenylalanine, a bioisosteric mimic of acid-sensitive O-sulfatyl tyrosine, was synthesized from l-tyrosine according to a novel route. Partial sequences of the recognition site of P-Selectin glycoprotein ligand 1 (PSGL-1), which contain (sulfomethyl)phenylalanine were synthesized on solid-phase. By fragment condensation, a sialyl Lewisx peptide conjugate containing a (sulfomethyl)phenylalanine mimic of O-sulfatyl tyrosine was prepared without destruction of the acid-sensitive fucoside bond within the saccharide side chain. Compounds of this type are of interest as sufficiently acid-stable potential inhibitors of P-Selectin in inflammatory processes.