COMBINED FMOC-ALLOC STRATEGY FOR A GENERAL SOLID-PHASE SYNTHESIS OF PHOSPHOSERINE PEPTIDES

A building block method for the SPPS of serine phosphopeptides has bee n developed using a combination of Fmoc and Alloc strategies. Alloc-Se r[PO(OCH2CH=CH2)(2)]-OH, prepared in a one-pot procedure from Alloc-Se r-OH, was introduced at the N-terminus of a sequence prepared by stand ard Fmoc-SPPS. Global cleavage of the allyl ester protecting groups fo llowed by coupling of a tripeptide fragment led to tau phosphopeptide, 1, which was not available by post assembly phosphorylation strategie s and is an important epitope of tau phosphoprotein in Alzheimer's Dis ease.