Mini review: Engineering hydrogen-bonded duplexes

Based on several simple, readily available building blocks, oligoamide strands carrying various arrays of hydrogen-bond donors and acceptors, i.e. hydrogen-bonding sequences, have been designed and synthesized. Detailed characterization indicates that these oligoamide strands associate via their hydrogen-bonding edges into doubled stranded pairs (duplexes), which are characterized by programmable sequence specificity and adjustable stability. Using these hydrogen-bonded duplexes as association units, supramolecular structures, such as β-sheets and non-covalent block copolymers, are obtained by simply mixing the corresponding components. Recently, by incorporating reversible covalent interactions into these hydrogen-bonded duplexes, sequence-specific formation of covalently linked structures has been realized under thermodynamic conditions, which has opened an entirely new avenue to the development of previously unknown dynamic covalent structures such as various block copolymers.