Deprotective activity of nanosized globular partially quaternized poly(tertiary amine)s in peptide synthesis
AbstractBifunctional polybases of the partially quaternized poly[thio-1-(N,Ndiethylaminomethyl) ethylene] type (Q(PTDAE),X, with X = percentage of N-quaternization) are able to catalyze various reactions including lipophilic reagents temporarily entrapped in the hydrophobic core of the globules. In this contribution it is shown that benzyloxycarbonyl (Z) and fluoromethyloxycarbonyl (Fmoc) protecting groups of peptides are cleaved at room temperature in a few minutes in an aqueous medium at pH 7,4. Deprotection was also effective when peptides were attached to solid supports of the Merrifield type provided a hydrophilic spacer arm of the poly(ethylene glycol)-type was inserted between beads and the built up peptide moieties. However, unhooking was observed when the hydrophilic spacerpeptide bond was an ester but not when it was of the amide type. The work shows that Q(PTDAE),X globules exhibit enzyme-like activity in a homogeneous aqueous medium and in heterogeneous systems as well.