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Supramolecular materials have been assembled using a wide range of interactions, including the hydrophobic effect, DNA base‐pairing, and hydrogen bonding. Specifically, DNA amphiphiles with a hydrophobic building block self‐assemble into diverse morphologies depending on the length and composition of both blocks. Herein, we take advantage of the orthogonality of different supramolecular interactions – the hydrophobic effect, Watson‐Crick‐Franklin base pairing and RNA kissing loops – to create hierarchical self‐assemblies with controlled morphologies on both the nanometer and the micrometer scales. Assembly through base‐pairing leads to the formation of hybrid, multi‐phasic hydrogels with high stiffness and self‐healing properties. Assembly via hydrophobic core interactions gives anisotropic, discrete assemblies, where DNA fibers with one sequence are terminated with DNA spheres bearing different sequences. This work opens new avenues for the bottom‐up construction of DNA‐based materials, with promising applications in drug delivery, tissue engineering, and the creation of complex DNA structures from a minimum array of components. [ABSTRACT FROM AUTHOR]

A novel biomimetic DNA analogue with fluorescence has been synthesized to generate functional supramolecular architectures. Experimental studies show that triaminopyrimidine nucleoside (2) undergoes a sterically controlled self-assembly into hydrogen-bonded linear tapes and hexameric rosettes. Self-association of the hydrogen-bonded triaminopyrimidine-cyanuric acid complex into elongated, rodlike nanostructures was shown by dynamic light scattering and transmission electron microscopy, suggesting hierarchical formation of higher-order, π-stacked assemblies. The hydrogen-bond self-assembly of the DNA analogue decreased the fluorescence of the nucleosides. This guest-induced fluorescence quenching can be used to develop DNA-hybridization probes. [MM.sup.+] molecular modelling and semi-empirical molecular orbital PM3 calculations (1) predicted the incorporation of triaminopyrimidine nucleoside into new types of artificial DNA strands and triplex formation with natural, complementary DNA strands containing thymine (1). Key words: hydrogen bond, self-assembly, DNA analogues. Dans le but de generer des architectures supramoleculaires fonctionnelles, on a synthetiser un nouvel analogue biomimetique de YARN fluorescent. Les etudes experimentales montrent que le nucleoside de la triaminopyrimidine (2) donne lieu a un autoassemblage sous controle cinetique qui conduit a des bandes lineaires on des rosettes hexameres reliees par liaisons hydrogenes. Faisant appel a la diffusion dynamique de la lumiere et a la microscopie dlectronique de transmission, on a pu ddmontrer que l'autoassociation du complexe triaminopyrimidine-acide cyanurique par des liaisons hydrogenes conduit a des nanostructures allongdes, en forme de baguettes, suggdrant qu' il y a une formation hidrarchique d'un ordee eleve d'assemblages par empilement π. L'autoassemblage par liaisons hydrogenes de l'analogue de l' AND diminue la fluorescence des nucleosides. Cette extinction de la fluorescence induite par l'hote pourrait etre utilisee pour developper des sondes d'hybridation de l'ADN. Des calculs de modelage moleculaire, [MM.sup.+], et des calculs d'orbitales moldculaires semi-empiriques, PM3 (1), permettent de prddire qu'il y aura incorporation du nucleoside de la triaminopyrimidine dans les nouveaux types de brins artificiels d'ADN et formation de triplex des brins naturels compldmentaires d'ADN contenant de la thymine (1). Mots-cles : liaison hydrogene, autoassemblage, analogues de l'ADN. [Traduit par la Redaction], Introduction Hierarchical assembly of low molecular weight building blocks has generated functional supramolecular architectures with high predictability. (1) Molecularly self-assembled photo-responsive systems were constructed by combining strong, directional, hydrogen bonds [...]