Coupled Conformational Equilibria in β-Sheet Peptide−Dendron Conjugates

A series of peptide−dendron conjugates, based on an intrinsically α-helical, alanine-rich sequence, were constructed to explore how the conformational equilibria of each structural element can be conformationally coupled. The interdendron spacing was varied from i, i + 4 ( 2 ) to i, i +11 ( 9 ) to probe how the nature of the dendron interaction impacted the conformational properties. These studies revealed an α-helix to β-sheet conformational transition that occurred in water for peptide−dendron conjugates 4 ( i, i + 6) and 8 ( i, i + 10). Chiral transfer from the peptide backbone to the dendron helicity emerges only in the β-sheet forms of 4 and 8, revealing a synergistic coupling of the conformations of both structural elements.