A preorganized β-amino acid bearing a guanidinium side chain and its use in cell-penetrating peptides.

Abstract

A cyclic β-amino acid (APC(Gu)) bearing a side-chain guanidinium group has been developed. The APC(Gu) residue was incorporated into an α/β-peptide based on the Tat(47-57) fragment, leading to an oligomer with substantial helicity in methanol that enters HeLa cells much more readily than does the corresponding Tat α-peptide.