A focus on a complex abiotic tertiary structure

In contrast to the many well-defined helical secondary structures of foldamers reported thus far, examples of tertiary molecular structures of foldamers remain rare with the development of such folded structures being still in its infancy. While the direct design of foldamer tertiary structures still presents a daunting challenge, a realistic strategy for developing unimolecular tertiary structures of foldamers involves covalently linking the molecular components of known quaternary structures of foldamers that have been reported in recent years. Wang et al. (S. Wang, J. Sigl, L. Allmendinger, V. Maurizot and I. Huc, Chem. Sci., 2025, 16, 1136-1146, https://doi.org/10.1039/D4SC07336C), by starting from a C3- symmetrical, hydrogen-bonded homochiral parallel bundle of three aromatic helices, used rational principles and molecular modeling to convert the trimolecular object into a unimolecular helix-turnhelix- turn-helix tertiary structure that represents the most complex abiotic tertiary structure known to date.